what DOHC heads will work on an M70? I want some options for upgrades and I am not really liking the 2v per cylinder SOHC heads.

I don't believe that anyone has found an interchange.

Contact Ed here www.mwrench.com

He has been working at it and is quite knowledgeable on the V12

Thanks, emailed him.

from what I have heard, there is, but no one I have asked so far knows for sure.

It is possible but I wonder if it is worth the $$. You can always get heads off the Mclaran F1 to fit the 850 and get a huge increase in power.

The reply from Ed that I got:



Hi:

Unfortunately, there is nothing that will bolt to the M70, The M70 is one of the hardest engine to modify and does not respond well to tuning efforts. There are many claims for more power but most are bogus. The stock heads have one of the worst exhaust ports and will not flow well even if ported. I have been involved with trying to design custom heads with 24 valves but at the end of the day it would cost over $100K for the first set, after that each set would cost about 30K-$50K.

The engine can not be simply bored out either. The cylinder walls are Alusil coated during casting and once that hardened coating is removed is scores easily, I have seen other Nikasil plate the bores with moderate success but is an expensive process, The cylinders can be sleeved but that is also an expensive process. Custom cranks cost over $4K each and have a three month lead time.

There is only two cam options at present, 1) 850CSI and 2) Schrick.

Can't change the compression ratios easily.

Another urban myth, the F1 V12 heads will NOT fit the M70, that engine is completely different in mechanical layout inside and only share the same bore spacings. (91mm)

Nothing is cheap when working on this engine.

You didn't say what you were trying to do or what your goal was. HP?

Sorry, don't have better news for you but this is reality!

Best Regards,

Ed
MWrench

The reply from Ed that I got:
I have been involved with trying to design custom heads with 24 valves but at the end of the day it would cost over $100K for the first set, after that each set would cost about 30K-$50K.

MWrench

That is what I was talking about. which is very close to the F1 head. The engine displacement can be increased with a powern increased to 440HP at the crank. I know atleast 2 people who have done it and 1 more being done. They were done by PowerPlant racing in South Carolina.

The other option is FI. There are several Twin Turbo cars I know of. Especially 1 I personally helped a tiny bit that produces 444HP and over 600 ft-lbs of torque at the WHEELS.

So what is your quest?

I'd like to know why Euro s50b30 heads couldn't be made to fit the block, with identical bore centers and similar water channels there must be a way. The challenges are the following:

1. M70 is belt driven, b30 is chain driven; along with single Vanos, making this work is the biggest headache; I suspect the only viable solution is converting the b30 head to cam timing, not easy and I'm not sure whether Vanos could be physically maintained with this setup
2. Increasing bore to b30 specs (86mm) will undoubtly require sleeving; the only cost effective method would be retaining stock b30 internals (pistons/rods), b30 pistons are designed to function in the Euro M3 block which is cast iron, M70 being Alusil; the stock S70 bore is 86mm but again wear issue using b30 pistons
3. Increasing stroke to b30 specs (85.6mm close to MF1 87mm), I'm not sure the M70 block has enough clearance to fit a custom stroker crank (from stock M70 75mm to 85.6mm) although I'm confident; the biggest problem is raising the block height to achieve b30 specs, a spacer and 2 gaskets could do the trick for 5-6mm but stock pistons may no longer function safely
4. The driver side head would have to be flipped and its camshafts flipped again since both cylinder banks are functioning as two paralel inline-6s in terms of firing sequence

It can be done, with ingenuity, patience and money. S50B30 engines are fairly cheap in Europe, 2 of them should provide many useful parts.

Regards,
Bruckner

I have been doing research on this for a while now and have come across a few options.

I have herd that it can be done but the problem is the driver’s side. You can use the non vanos 92 M50 heads. I have herd that the guy who owns the Power Plant has a few DOHC V12 M70s with 600+hp NA. Supposedly he has the info and has a full book on it and how to do it. If you ask him he will say no or he doesn't know what you are talking about but do the research and run questions that are intelligent by him and he will respond. Contact me for more info if needed.

I have herd that the guy who owns the Power Plant has a few DOHC V12 M70s with 600+hp NA. Supposedly he has the info and has a full book on it and how to do it. If you ask him he will say no or he doesn't know what you are talking about but do the research and run questions that are intelligent by him and he will respond.

I'm rather skeptical. I don't see how a stock block M70 could be made to push beyond 6 liters of displacement, consequently I have trouble believing even 500hp could be obtained using M50 heads which are good but nowhere near the flow characteristics of S50B30 heads. The benchmark is the MF1 engine, with combustion chamber design and port arrangement similar to the B30, it's the optimal solution and I doubt 600hp could be reached without BMW's development and testing capabilities.

If someone did it however, I'd love to know how! And if a book has been published, why would its author ignore its existence?

Regards,
Bruckner

I'm rather skeptical. I don't see how a stock block M70 could be made to push beyond 6 liters of displacement, consequently I have trouble believing even 500hp could be obtained using M50 heads which are good but nowhere near the flow characteristics of S50B30 heads. The benchmark is the MF1 engine, with combustion chamber design and port arrangement similar to the B30, it's the optimal solution and I doubt 600hp could be reached without BMW's development and testing capabilities.

If someone did it however, I'd love to know how! And if a book has been published, why would its author ignore its existence?

Regards,
Bruckner


I didn't say anything about 6 liters. I don't know about that. M50 heads are just the same as any S5* heads. They just need to be worked more. M50 non vanos heads are used for simplicity.

It is not a published book. Its more like a write up that this guy keeps in his safe and only shares to certin people.

I didn't say anything about 6 liters.

Of course you didn't! No matter how you look at it, a 5.0l V12 will NOT achieve close to 600hp, enlarging displacement is the only solution to making serious power gains! Keeping the stock M70 stroke/bore of 75/84 with M50 heads and you get a pair of 2.5l inline-6s making less than 200hp each, a 50% increase in power over this will need more than porting and other tricks, not worth the hassle of making the combo work. Let me put it this way, the M70 block doesn't allow for an increase in displacement over, say, 6-6.2 liters (limitations to bore and deck height increase for longer stroke), at this level the most advanced heads in terms of port design and flow characteristics ever made are the M3 units, even using these ultra advanced heads 600hp would be a long shot, if BMW and their extensive development capabilities couldn't optimze beyond 620hp using heads very similar in design to their own available S50B30 heads, I doubt anyone else can pull it off using inferior heads such as the M50s.

As for keeping the secret recipe in a safe.. lol! The only serious upgrade is using S50B30 or even S50B32 heads (double vanos, more complicated and donor engines are more expensive), it can be done, I need not be secretive about that! :)

Regards,
Bruckner

Wow you are stuck on using S50 heads. It seems like you are very narrow-minded on this subject so I will stop giving out info that has been researched and proven to work. Insted of asking how etc you just go out and say no that will not work.

If anyone wants more info just PM me. I am not going to spread it on the forums anymore.

Funny thing is that the difference between all of the different heads is very minor between the M5*/S5*.

Funny thing is that the difference between all of the different heads is very minor between the M5*/S5*.

No way!! The volumetric and combustion efficiency characteristics are vastly improved on the M-developed S50s, with fully machined combustion chambers/ports, individual throttles per cylinder and an unsurpassed specific engine torque/capacity (all of which are mostly due to head design), the comparaison is totally unfair, speaking of minor difference in head design is just wrong.

If I were to attempt this complicated project, I would go for the best units out there, otherwise it wouldn't be worth the effort, maybe that's narrow minded?! I'm not saying fitting M50 heads wouldn't work, I'm saying it's so suboptimal it's not even worth the expense.

I will stop giving out info that has been researched and proven to work.

Whatever! How could you stop giving info, you didn't even start, unless you consider rumors about someone who supposedly did it to be valuable technical info? Please..

Regards,
Bruckner

No way!! The volumetric and combustion efficiency characteristics are vastly improved on the M-developed S50s, with fully machined combustion chambers/ports, individual throttles per cylinder and an unsurpassed specific engine torque/capacity (all of which are mostly due to head design), the comparaison is totally unfair, speaking of minor difference in head design is just wrong.

If I were to attempt this complicated project, I would go for the best units out there, otherwise it wouldn't be worth the effort, maybe that's narrow minded?! I'm not saying fitting M50 heads wouldn't work, I'm saying it's so suboptimal it's not even worth the expense.



Whatever! How could you stop giving info, you didn't even start, unless you consider rumors about someone who supposedly did it to be valuable technical info? Please..

Regards,
Bruckner

You are talking about the Euro heads off the Euro S50/52. The US S50/52 is pretty much a bored/stroked M50/52 with a different tune. That is why he was saying there was little difference.

Was looking for a different post and saw this one.

1) Henry Lawrence (a personal friend and associate) has NEVER done a DOHC modification of the M70 series V-12. He has done cad drawings of a proposed head(s) that would have to be cast in two pieces and plasma welded. Due to lack of money or enough interested people with money, this was never taken beyond the drawing stage! No prototypes were made and no engines were ever put together.

Henry has recently completed a N/A 6.0L engine with 11:1 compression, trick custom cams, shortened intake runners bored out throttle bodies, headers, lightened rods and results were 407 HP at the wheels, this would yield about 480 at the crank. That is a lot of work (read $$$$$) for those numbers!

2) The M70 series engine is NOT the same as the F1 engine and F1 heads will NOT fit! The only thing that is in common with the two engines is the bore spacing of 91 mm. Cooling and oiling passages are vastly different and not at all compatible. This was explained in the BMW engine book by Dr. Karlheinz Lange.

3) The maximum displacement the M70 series engines can be taken to is 6.1L but most stop at 6.0L 86mm X 86mm Bore and stoke. The limiting factor is which was stated in an earlier post is the bore spacing (91mm) and deck height. There have been claims of a 7.0L engine but that is plain and simple BS! At 91mm bore spacing that only leaves 5mm between cylinders, to get 7.0L with a 86mm bore, the stroke would have to be over 104mm. At 86mm stroke in Henry's 6.0L engine the wrist pin is right at the oil ring land and the stock rod is already to short, there would be no piston skirt. It is just impossible to get 7.0L out of the m70 series engines!

4) The m5x/S5x heads do have the same head bolt pattern but that is were the commonality stops. Oil drain backs don't line up, Cooling passages might work on the passengers side but would not on the drivers side. Don't forget, the drivers side has to be rotated 180 so the cam drive is at the back end of the engine on that head. The entire cam drive would have to be machined off and redesigned. Even the passengers side would have to have extensive modification for the chain drive to line up and then all that has to sealed in an oil tight cover.
The M70 does not use a belt cam drive, it is a single chain! Forget Vanos, this would require a precision front cover to hold the Vanos mechanism and would have to be fabricated on the drivers side and redisigned on the passenger side.
Bottom line, the M5x/S5x could be used as a reference for design of a new set of heads but will NOT bolt on and work or can't be modified to work!

5) There is an effort going on here on the West coast to design and build a set of heads but I will not know for a few more months if these will become reality, if they do work and can be made the price will be >$50K for the set.

6) BMW did in fact test a M72 version that was a DOHC engine but it was never brought into production, it was not deemed suitable for a luxury sedan. Again this is directly out of the aboe mentioned engine book, It is indeed a shame that BMW didn't bring this to production



Hope this helps

Ed
MWrench

After researching the M70 for nearly two years I decided to use it as the aftermarket powerplant of choice for my 3000lb semi-racepurpose 84 Trans Am. I list the benefits hereby and the faults, as well why I chose it.


I'll be honest, its a V12. Its ounds like one, it looks like one, on a bad day, it runs good.
Low weight
Incredible torque curve. Stock, the M70 puts out nearly 400 pound feet of torque and does it so smooth its nuts. Perfect for a car where wide ratios are beneficial and low weight is a reality.
Custom programming and excelelnt exhaust have been proven to put it at nearly 350 HP crank. MAF's should pick up another 20 across the powerband, and cam's can easily complete the 400 to 410 horse goal. But Im not camming it. Why?
A well though out TT system in my chassis is available and producable and I can get sponsorship. The 300 Horses will turn into a conservative 500+ at the wheels, and the torque should allow me to pull semi's if need be. Dollar for dollar, this engien begs for FI.



Now I will list the detriments.


The head design rivals that of the flathead Ford. It is hideaous. I doubt anyone will ever get a fix to let this engine even see 450 horses out fo 5.0 liters
It is Alusil. It isnt very machinable.
An LS1 quite frankly will blow the doors off of it in sheer muscle performance and do it at less than the price of a set of cams and a aftermarket fuel system. It will not beat the M70 in terms of overall..."pinahce". I beleive the v12 will give my car daily dirvability, fuel consumption that is livable, and V12 sound while still enabling my car to be very,very fast in most all but the most advnaced track conditions.
There are no DOHC heads for the m70. I even looked at 325iS m20 heads. They outflow M70 heads. You want an upgrade? Thats your avenue..but still
Wait for the 760 motor to be available. It should be able to push 600 horses NA heavily modded and around 11 to 1200 horses on turbos. Its sick, beyond our m70's wildest dreams

Huh? My car is being converted to a 6L (Initially M70 5L) right now and a couple of extra mods. There is a way to get 550+ hp out of the NA motor but it will not pass emissions. I am looking forward to a emission legal 450+ HP at the crank. I am also getting a 12lbs lightweight FlyWheel installed to reduce the driveline loss.

The car should be completed by September. I will post Dyno and dragstrip results then.

I have not seen a single documented instance of an NA m70 seeing over 550 at the crank, I dont care if its got so much cam raw flame shoots from the headers...I have never seen a single reliable documented case of a <+= 6.0 liter m70making 550 at the crank. I seriously wish I would....see above post. However, 450 passing emissions is nice, although, post up those calibrated dyno sheets when you get them and make sure you state whether its acutal or SAE.

well, 434 is believable, but I dont see how they are pulling 520 Horses....Ive SEEN the flow numbers off of m70 heads

Makes me feel good to know its out there, and besides, we all act like 434 horses is nothing, out of a 6.0, its pretty decent. The LS1 has spoiled us, a 6.0 LS1 makes over 400 crank factory, if you wring it out the way those are you are pushing over 650 horses crank...

434...500...530 horses are all ggod enough numbers to actually be very competitivi..especially with the m70's torque curve

PS....I wish I knew some of your friends :)


Ive only been in an 8 once, and he sold it. It was bone stock...and very awesome

just watched the video too..awesome...444 horses on half an atmosphere is impressive, the other 5.0 liter favorite is the mustang, its peak is 575 at crazy stupid boost stock, so this is by far exceeding it, and doin it in a very nice way. I cannot wait to get mine set up

MWrench, in all due respect, I see nothing in your post that I haven't outlined in my post #7, and having similar knowledge we disagree on the feasibility of this project, no one will deny the difficulty level but compared to making a single run off custom head design would be extremely expensive. Two members, including yourself, mentioned the impossibility of bolting the F1 head, I'm sure you're right but I can't see how someone could get their hands on F1 heads anyway, if at all available to the public! Like I said, in terms of combustion chamber design and port arrangement, the F1 head is very close to the 3.0l Euro M3 head, water channels line up, doubts remain about one oil gallery which appears offset however there are greater difficulties, mostly getting around the chain vs belt drive and the flipped head and camshafts arrangement on the driver side.

Although an excellent observation, I'm afraid this claim of yours is incorrect: "Cooling passages might work on the passengers side but would not on the drivers side." The stock V12 block has mirror water channel arrangements from one bank to the other (I will attempt to post a pic to show this), by flipping the driver side head the channels are lined up, only problem remains reverse firing sequence and incorrect camshaft drive alignment.

I remain convinced this project is feasible although very ambitious.

Regards,
Bruckner

Does anyone have some good pictures of the surfaces of the proposed 4-valve heads? I've seen a few, though not very good the coolant and oil passages appear to line up with the V12 block.

Two members, including yourself, mentioned the impossibility of bolting the F1 head, I'm sure you're right but I can't see how someone could get their hands on F1 heads anyway, if at all available to the public! Like I said, in terms of combustion chamber design and port arrangement, the F1 head is very close to the 3.0l Euro M3 head, water channels line up, doubts remain about one oil gallery which appears offset however there are greater difficulties, mostly getting around the chain vs belt drive and the flipped head and camshafts arrangement on the driver side.


Even if the F1 heads would work, where would one possibly ever get them. I doub't BMW even has them listed in their parts database.

If you are that bent on v12 four valves, wait for the 760 engines to become available. It would probably be cheaper to buy one from BMW than fabricate a set of heads

however there are greater difficulties, mostly getting around the chain vs belt drive and the flipped head and camshafts arrangement on the driver side.

From your comments, I don't think that you have seen a M70 V-12 up and close! The M70 does NOT use a belt to drive the cam shafts as you stated! They are chain driven and a single row chain at that!

I have re-built half a dozen or so M70 including a couple of 6.0L that were bored out and sleeved, they (the 6.0L) will make about 420-450HP MAX!

I have M70 blocks, M70 heads, S54 heads and various gaskets, and have had them sitting on each other! I have invested a lot of time and money into this quest and my comments are based on a few years of research and sole searching into this idea!

From your comments, I don't think that you have seen a M70 V-12 up and close! The M70 does NOT use a belt to drive the cam shafts as you stated! They are chain driven and a single row chain at that!

Arhhh! Right! Correct, I've never seen the M70 in the 'flesh', however I couldn't see how mating head/block could be done without first resorting to cam timing, custom fabricating oil tight galleries and covers for the mismatch chain drive would be more than a challenge, and that's just the beginning of it, cam timing seems to be much more flexible than chain timing.

Regarding S54 heads, besides having the same bore centers as both the M70 and b30, which part is giving you trouble? Water channels seem to line up perfectly (on the b30 at least, no idea of the s54, please confirm), how about oil galleries? Have you tried fitting a factory b30 headgasket to the M70 block, same problems as the S54? Please explain, I'm very interested.

Regards,
Bruckner

I have M70 blocks, M70 heads, S54 heads and various gaskets, and have had them sitting on each other! I have invested a lot of time and money into this quest and my comments are based on a few years of research and sole searching into this idea!

Can you post some good pics of the 4-valve heads? I would be interested to see them and it would also make the nay sayers silent.

I tried to post a picture but I guess I don't post enough and wasn't granted peermission to post.

I will do so later and put up the picture on my website. I will try to post the link without the at sign and maybe that will go thru.

I would be interested to see them and it would also make the nay sayers silent.

Oh classic! Try showing interest in a challenging project, focus on the solutions instead of the problems, request further info from those in the know, and voila, you're a naysayer! Brilliant! Dude, don't ever get out of your narrow bubble, you could get scared.

If there's an ounce of good faith left in this discussion, I'd like to know whether the problems encountered with the S54 heads were the same on the b30 (early 3.0l Euro M3 e36) heads; my point from the start was that b30 design is the only solution, even if that means working around the oil gallery problem, removing Vanos and repositioning the drive on the driver side head, converting to cam drive isn't impossible for someone with ingenuity and ressources, 50K$ for new design heads sounds like a nice budget to work around.

I never implied this project is simple, nor am I trying to downplay some people's efforts in actually trying things out, just challenging the seeming consensus that it can't be done.

Regards,
Bruckner

Well guys, lets analyze engine power production...

Engines make power by processing air.

The theoretical max power an engine can make is 100%VE times RPM times a few other numbers

Then we account flow amounts and ratios
Atmospheric pressure, and VE/RPM charts

From this informatrion, power production can be pinpointed and plotted with striking ease from a home PC

But we still look at..MAXVE and RPM, theres no way around it

In another words, you have four billion vlaves, but in two revolutions the max a 5.0 liter engine can take in in is 5.0 liters. You can add maybe 10 percent to that in the real world for acousticeffects and ramming, but that wont occur over all RPM

So negate the whole four vlave thing..it doesnt matter..you can use more vlaves, por pressurize, either way, a street engine is going to have a max power, if you increase beyond that..you start getting diminshing return

Oh NOES! Just turn up the boost and squeeze more NAWS!
Irrelevant, yes, insane boost pressures, 107+ Octane fuels, alcholhol injections, nitrous etc can allow you to run on the stupid edge of insantiy, but for STREET

Previous money wasters have shown that with relatively mild headwork and a good turbo or very good heads (think Guerney Eagle F1's) and NA..max power on 5.0 liters (thanks to the mustang retirement spenders out there :D) hovers around 550 to 600 horsepower. I have personally seen 575 on 19PSI...bringing it to 24 PSI over 13.1 PSI atmosphere only yileded about another 35 horses and a lot of breakage..It has to do with mass flow and the wayfluids reaact under heat and pressure and theier gaseous compositions

so take that 575 number as a damn lucky to acheive..oh yeah..IM talking wheel here...so, on the mustnag add about 40 horses to that...which puts you at over 610 flywheel..or the 500 Ive seen with rediculous heads and exhaust flaming cams...and you wind up witht he same

A V12 will produce better power than a V8...but...mainly in "area under the curve" situations, peak will remain similar

So how does this apply?

We can put any head we can conjur on the V12, and what does other peoples spending teach us?

With BMW drivetrain (50 horse loss or more), expect around 450 to the wheels streetable NA or around 550 at best biturboed (if you dont do two on a v12 your insane) Now, can you broe and stroke and go nuts? yes. But what does a McClaren F1 6.0 lay down ....ahh...divide that by 6 and multiply by five and theres your best expected whp for the V12 with its deep stroke to bore truck engine ratio..

I dont see how the 4v head is worth it. Turboes put you at more or the same for less...and really good headwork I know Ive seen charts for 400 on the ground from the M70..if you wanna chase that 30 or 40 whp, go lightweight drivlein components and a single piece drivehsaft like the Z34 guys..

Liek I said, wait for the 6.0 to become more avialable..that thing is totally a wet dream of street V12's

Oh classic! Try showing interest in a challenging project, focus on the solutions instead of the problems, request further info from those in the know, and voila, you're a naysayer! Brilliant! Dude, don't ever get out of your narrow bubble, you could get scared.

To the contrary I actually think this swap is very possible. I have some pics of a 4-valve head and it appears that both the oil return galleries and coolant passages line up with the V12 block perfectly. But the pictures of the head are not of the best quality or from the optimal angle so it's difficult to tell conclusively one way or another.

It also sounds like MWrench has actually placed the 4-valve head on the V12 block so I tend to take his word for it but would still like to have some more info.

BTW Jaguar V12's are also 2-valve SOHC and people have sucessfully adapted the 4-valve 6-cylinder heads to the V12's. Some companies even sold such conversions though it was expensive.

www .jagweb.com/aj6eng/stretching.html

Comparisons with other 5.0L engines isn't a good one because the V-12 is not easily changed. The aluminum cylinder bore required either sleeving or iron coated pistons and higher compression pistons aren't available! 8.8:1 compression won't cut it! The S70 engine (CSI) had 10:1 compression and more agressive cams but again only Schrick make a slight upgrade from there. Nothing else! You can not go to your friendly Summit Racing Store and get parts for the V-12.

The head is a really bad design, the intake side of the head is OK but the exhaust is BAD! Many have tried to get the exhaust side to flow better with a lot of work but still will not come up to more then 70% of the intake side!




Go to the link below, it is a cut way view of the head I did some years ago in the study of the head for porting purposes, there isn't much material to work with.

www dot mwrench dot com forward slash Whitepapers and click on V-12 head.

Tonight I will put up some pictures of the head gasket comparisons and the S50 head gasket laying on the V-12 block, Will psot the pictures in the same group.

Enjoy

Missing my point...Im discussing theroetical max power fo rthe engine..has nothing to do with CR or heads or anything else. Studying theoretical max only looks at displacement...what iM saying is;

Th 5.0 V12 has already been brought closer to its max than its head flow capacity would suggest. It isnt economically feasible to bring more power by head changing that turbocharging

I have some pics of a 4-valve head and it appears that both the oil return galleries and coolant passages line up with the V12 block perfectly.

Great! I'd rather be a blind optimist than a naysayer, I'll take your word for it, although I would appreciate Mwrench experience on this, like I said the B32 or S54 may not fit, but from the start I believed the B30 is the only benchmark to work with. It seems possible to achieve identical bore/stroke than the B30 (maybe the 85.6mm stroke is pushing the limit of deck height increase using headgaskets with the stock M70 at 75mm, or so I thought, Mwrench mentioned 86mm was done already), with sleeving and a custom crank this means stock B30 rods and pistons could be retained.

Regarding the argument in favor of turbocharging, it makes perfect financial sense, in hp figures NA engines are no match for turbocharged equivalents (in peak turbo F1 times 1200hp required only 1.5l displacement!), however insane amounts of money have since been poured into NA engineering for a reason, power delivery and response is better achieved with a NA, big power is cheap with V8s, quality power means refinement and character, for this reason alone the myth of the NA V12 is worth the money.

Mwrench, thanks for the pics, I'm looking foward to hearing more about your experience. In addition to the topics above, can you comment on head design of the S70 compared to the M70?

Regards,
Bruckner

OK, the pictures of the block with a S50 series headgasket on it are up on my website, same address just look for the IMG_5920 series of JPGs. Clearly this is where you will see that it isn't a "direct" bolt up and no, the oil drain back and water holes do not line up perfectly and would reauire a substaintial amount of work to get a oil tight and water tight fitting, not impossible but a lot of work. It has to be done to the head bedause the block has a very high silicon content and very difficult to weld. The only oil supply to the M/S70 head is that slot that is visible from one of the head bolts, with a single cam little oil is needed.

The S70 head is exactly the same as the M70, no changes what-so-ever, the S70 is 5.6L 86mmX80mm B/S, rated at 380 HP. Exhaust manifolds are also indentical, the intakes have a different part number but no one knows why the internal dimensions are identical.

I do agree on one point, you want HP from the BMW V-12, turbo charge it, don't go crazy thou, the engine is NOT very durable!!! The heads bolt are very small (10mm) and the clamping force is not very high. The slightest lean condition will burn the iron coating off the pistons and you will have a rod thru the block in short order! We have had some NOX guys melt them down big time.

The next generation V-12 engine (760Li) probably will not see much application in performance applications because it is it direct fuel injection, valvetronic system that varies valve lift and timing (the computer is everything). It has longer bore centers (98mm vs 91mm) and has the capability to go to 7.0L. Bentley uses a derivitive of this engine. Very low production volume and no after market parts! I am sure you will see some high $$$$$$ build-ups/conversions from German tuners but for the average guy---forget it---

Yeah, but you can buy the engine for less thn 50K

as far as direct injection and multiphase camming, we'll have a firm aftermarket handle on that one day as well

right now, the 435 horse 6.0 liter blows the doors off of evven turbocharged v12's when it comes to all around power...has anyone ridden in or driven one? :eek:

Oh, and I am with you on the NA power, but if I am going to spend that much money, id rather start with a ferrari

http://www.boggbros.co.uk/gallery2.html

found this on another forum ... cool!

Do you have some more info on this? Was anything more posted on the forum?

OK, the pictures of the block with a S50 series headgasket on it are up on my website, same address just look for the IMG_5920 series of JPGs. Clearly this is where you will see that it isn't a "direct" bolt up and no, the oil drain back and water holes do not line up perfectly and would reauire a substaintial amount of work to get a oil tight and water tight fitting, not impossible but a lot of work. It has to be done to the head bedause the block has a very high silicon content and very difficult to weld. The only oil supply to the M/S70 head is that slot that is visible from one of the head bolts, with a single cam little oil is needed.

On picture IMG_5920.JPG the 5th bolt hole from the left, is that the slot you are referring to?

On the same pic, are the lower oval shaped holes the oil return galleries?

Could you post pics of the head surfaces if you have them lying around?

I think this swap looks rather feasible.

Also do you know if other 4-valve I6 engines from BMW also share the same borespacing an bolt hole locations?

Yes that slot is the oil supply.

If you look at ing_5923 you will see that the ovals on the engine block are larger then the gasket holes for the oil return on the six cylinder head. The casting is similar to the gasket and as I mentioned the head would have to be welded to make a seal in these and other areas.

I have never said that it wasn't feasibile or possible BUT sealing the head to the block is only the tip of the iceberg! The cooling issues (routing and water flow, water pump mounting, thermostat(s)) and the big one is the cam drive system, very complex issues, custom cams etc. drive up the cost. Throw enough time and $$$$$$ at it and it can be done. Also as I mentioned there is an effort going on now to do a custom head design using the S54 as a model.

I have to dig the M50 head out and will take some pictures later.


BMW little sixes all share the same bore spacing (91mm)

HTH

M50 heads on the M70

Look at this picture guys, it appears that all they did was just move the head over to opposite side without swapping end to end. The valve cover is a dead give away!

This would mean that they are using the exhaust ports as intake ports on the drivers side (US of course)

The oil drain back holes would be on the top side of the head and have no where to go!

Nice idea but not practical! Just won't work!

its doable, pull the triger man

MWrench:

Would you happen to have any flow numbers for the stock 2-valve heads?

Also how similar are they to the old 2-valve I6 heads?

Stock two valve heads produce flownumbers indicating a max of bout 400 hp, exactly what we see in practice.

New here but doing a modded V12 project of my own hence I have found this thread......

I'd be interested in knowing what people who are turbocharging their V12 are planning to do with their heads and cams as this is the route I am going.

IN my experience for turbo engines only the exhaust side is touched

This is because the exhaust side is so much less efficient than the inlet...... but what about cams or does everyone stay below 6100prm?

so much less efficient doesnt even scratch the surface onthe m70

Cams , I wouldnt recommend. To much overlap / duration for a turbo. Custom grind with a shade more lift would be nice though

The problem I have is that I want the motor to spin to 7000rpm minimum to make the most of the package I am using and I do not think the std cams can go up that high even with M3 springs.

what package?

I am building the car from scratch and its going to mid engined and light, also I am using a Porsche GT3 box... result is that I need the engine to produce power higher up and thus also have more BHP than torque.

I'd be very interested to learn more about your engine.

if you wanna chase that 30 or 40 whp, go lightweight drivlein components and a single piece drivehsaft like the Z34 guys..

Liek I said, wait for the 6.0 to become more avialable..that thing is totally a wet dream of street V12's

And that is whare I am at.

A 6L M70 with Lightweight Flywheel (12.5 lbs as opposed to 23 lbs Oem) and High Torque Clutch Setup (a six-puck ceramic/semi-metallic set-up rated at 700bhp and 800 ft/lb of torque) with a Custom Driveshaft optimally balanced.

With a 46% decrease in flywheel inertia, the mass loss on the flywheel allows more engine power to be used to accelerate the vehicle rather than the flywheel. Although a lightweight flywheel does not make the engine produce more horsepower, it does transfer more of that power to the wheels. It will give better throttle response and a harder "pull" out of corners.

With 295/35x18 tyres, a 3.15 diff and a 4.23 first gear ratio, this equates to a 240lb loss of vehicle mass, or approximately equivilent to a 25bhp power increase seen by the car from the engine, with less strain on the engine components, especially the crankshaft.

Here are some pictures:

Engine (Before Intake Heatshield and lowered filter):

http://members.roadfly.com/faisal_in_laurel/Engine1.jpg

Clutch:

http://members.roadfly.com/big8bmw/f8.JPG

Flywheel:

http://members.roadfly.com/big8bmw/f7.JPG
http://members.roadfly.com/big8bmw/f5.JPG

Clutch and Flywheel Togather:

http://members.roadfly.com/faisal_in_laurel/ClutchFlywheel01.JPG

SS Fuel and Brake lines (These DO NOT add any power. LOL):

http://members.roadfly.com/faisal_in_laurel/BrakeFuel.JPG

For all this Go-Go power I wanted to be able to stop better as well. Thus the US spec brakes left and Motorsport Floating Rotor CSi brakes were installed. This gives a 12+ feet of braking advantage. Does not sound like much but 12 feet is 12 feet in a panic situation.

May I ask is your intake in the picture modified to give you an chamber double the size as it looks? and if so what results did you get from this mod?

I'm also ditching the std flywheel and have bought a tripple plate 7.5in superclutch and will be making a flywheel to suit.

What other mods have you done to your engine as it looks very impressive with 450bhp.

What other mods have you done to your engine as it looks very impressive with 450bhp.

Well! I have Schrick Cams, bored out throttle body, Removed Stock Airbox to get DownDraft CAI, MAF from 325, X-Pipe exhaust with Center resonator removed and EisenMann Race Exhaust System.

Well! I have Schrick Cams, bored out throttle body, Removed Stock Airbox to get DownDraft CAI, MAF from 325, X-Pipe exhaust with Center resonator removed and EisenMann Race Exhaust System.

How did you go about converting the AFM based M70 to a MAF system? I've been considering it for my M30.

Split Second has a kit..or you can use the analogue volt output Ford 4.6 liter 92-95 MaF

How did you go about converting the AFM based M70 to a MAF system? I've been considering it for my M30.

Using Split Second.

Split Second has a kit..or you can use the analogue volt output Ford 4.6 liter 92-95 MaF

Could you please elaborate on the Ford option? I have seen the slit second deal, and I am afraid it looks like an awful lot for a D->A converter.

Fords, many of them at least, mass airflow meters use an analgoue 0-5 volt output...makes them very nice for conversions...now the 4.6 (cobra) is what they use on the S38..you have to look at the horsepower numbers..they are about the same :rofl:...anyway

You can just mount the sensor in forn of your existing sensor then map the analogue outputs of both on a dual trace oscilliscope. If they are close enough, it will work...remember, the MAF will never be identical because its a more powerful and exact tool than the AF sensor

Is a HPC ceramic coating better than niksil for the M70 cylinder walls once bored to 6.0L?

Any turbo kits recommended for a 6.0L M70?

Anybody willing to share the cost of of R&D to test different 4V head options on a M70. I found a shop with tons of BMW heads in-house to test at $85/hr. They can provide estimates after a few hours of research and of course could do the machining/welding as needed. This could help put this issue to rest. I thinking an estimate on fitting a M3 or M50 head would be a lot cheaper than designing new ones. Besides why reinvent the wheel. Let BMW do that. Contact me if inteseted. Happy driving.

Is a HPC ceramic coating better than niksil for the M70 cylinder walls once bored to 6.0L?

Any turbo kits recommended for a 6.0L M70?

Anybody willing to share the cost of of R&D to test different 4V head options on a M70. I found a shop with tons of BMW heads in-house to test at $85/hr. They can provide estimates after a few hours of research and of course could do the machining/welding as needed. This could help put this issue to rest. I thinking an estimate on fitting a M3 or M50 head would be a lot cheaper than designing new ones. Besides why reinvent the wheel. Let BMW do that. Contact me if inteseted. Happy driving.

I am not sure about the first question.

As for turbo, it really depends on what chassis the M70 6L is going into. I was almost there with my Twin Turbo setup for the 860 but there is not enough room for proper sized turbo. I bought a set of Garrett GT 28 RS Hybrids but they were still undersized. Thus I had given up the idea of the Turbo 860. I even have the low compression Pistons (9.0:1) and Exhaust Manifolds for sale. Maybe next time I will consider a Twin S/C setup at a low boost.

There are no Turbo kits available for the 6L but there are some success stories with Turbo setups with the 5L M70 Stock Motor.

Fords, many of them at least, mass airflow meters use an analgoue 0-5 volt output...makes them very nice for conversions...now the 4.6 (cobra) is what they use on the S38..you have to look at the horsepower numbers..they are about the same :rofl:...anyway

You can just mount the sensor in forn of your existing sensor then map the analogue outputs of both on a dual trace oscilliscope. If they are close enough, it will work...remember, the MAF will never be identical because its a more powerful and exact tool than the AF sensor

I don't know. I am having some trouble finding the voltage output/airflow tables for the BMW AFM. I found one for the (I think) MAF you described, but the BMW unit's figures are eluding me, especially since I can't find the Bosch PN.

Thats why you plumb one in series of the VAF and plot it

Faisal, where did you get the flywheel and clutch?? I want that setup!!
The mods to the intake are interesting as well, I was planning on building a new intake this winter with 12 individual downdraft throttle bodies right down the middle. I don't have the hood clearance issues you guys have lol.. I'd post a pic of my setup but the forum doesn't allow me to - haven't figured out why yet..
There's a shot here though
members.core.com/~sysadmin/personal/GTO-engine-Aug0004a.jpg
Chelle

Faisal, where did you get the flywheel and clutch?? I want that setup!!
The mods to the intake are interesting as well, I was planning on building a new intake this winter with 12 individual downdraft throttle bodies right down the middle. I don't have the hood clearance issues you guys have lol.. I'd post a pic of my setup but the forum doesn't allow me to - haven't figured out why yet..
There's a shot here though
http://members.core.com/~sysadmin/personal/GTO-engine-Aug0004a.jpg
Chelle

Hello Chelle,

Your engine looks fantastic.

The Clutch and Flywheel are from Phoenix Motorsport of UK. Here is the contact E-Mail and website. The Owner is Gerry and you can use me as a referance. However, their Website is being redone.

E-Mail: info@phoenixmotorsport.co.uk
Web Site: http://www.phoenixmotorsport.co.uk/

Hope this help.

Thanx for posting Faisal!
and thank you for the compliment
I spoke to that guy a while back and was going to buy the one flywheel he had left - he told me first with the money gets it and offered to bring it to mwrench, and I didn't hear from him again so I assumed he sold it..
I'll try contacting him again..

Maybe he'll appreciate that I made our car RHD.. lol
Chelle

Chelle,

I think he does those in batches of five. They are selling like hot cakes as this really wakes the car up as far as accelaration. Contact him again. He has several options for the clutch. Pick what you want depending on your need.

Cheers.

PS. RHD...I am sure he will. We do share a very funny story when he visited me in the US with his RHD 850CSi and we got pulled over by the police.

this is all good info..as I am sure I will have the 6 speed someday

Great info. thanks. Even if I have an auto. I will have a 6 speed CSi one day. Maybe when the Navy send me to Europe next time. For now I have to putter away on my 91 850i with Dinan chips.

How did you go about converting the AFM based M70 to a MAF system? I've been considering it for my M30.

The M70 series engine IS MAF based! Never was AFM on a M70 early models used Bosch hot wire and later M73 used Siemens thin film style.

You can substitute a '91 325 MAF which is larger in diameter which will change the MAF reporting so that it will match larger injectors better, works well with 6.0L engines and turbo applications.

HTH

I am looking into boring M20 throttle bodies or putting bored 75mm E36 throttle bodies on the 70 engine. How big are M20 TBs stock and how far can they be boreed out to? I'd like to put 1 throttle body per cylinder and the M20 and E36 throttle bodies seem to be a lot cheaper and more available than the M70 ones. Any thoughts on this configuraton.

I am looking into boring M20 throttle bodies or putting bored 75mm E36 throttle bodies on the 70 engine. How big are M20 TBs stock and how far can they be boreed out to? I'd like to put 1 throttle body per cylinder and the M20 and E36 throttle bodies seem to be a lot cheaper and more available than the M70 ones. Any thoughts on this configuraton.<P><P>I am interested in how you plan to operate the throttle bodies since the existing DK units are controlled by the EML control unit. Are we going with six EML units wired in series? And how will you get the PWG to send signal to all six EML units?

E31Guru

I have 2 thought on the matter:

1. Modify the throttle bodies to use mechanical linkages instead of the drive by wire EML. Then chain the throttle bodies together to run a Mechanical fuel injection setup using bank fuel injection.
This option of course doesn't provide the best fuel management optimization but is very cost effective.

2. Rip out all of the electronics and install a Haltech EMS for around $1000 which is setup to run various 12 cylinder configurations through a PC. This provides optimal results but cost more to setup. All though oncw its running all your fine tuning can be done via computer instead of playing with linkages.

That said, by adding individual throttle bodies, it has been argued that I wouldn't really increase HP, torque or air flow considering the head can only breath so much on the intake side. Some have argued I may even lose low end torque. I don't know anyway to know for sure without trying a before and after dyno. If Chelle or someone else considering doing it beats me toit perhaps they can shed more light on it.

Also as I mentioned there is an effort going on now to do a custom head design using the S54 as a model.

Is there an update on this initiative?

Regards,
Bruckner

I too would like to see an update. i cant imagine it though, the 6.0 is gettign to be 4 years old, is it not?

hi guys
i found Great info about m70 head on this topic
very soon i will work on new project for mid v12 m70 engine with audi 016 girbox

and...

checkout racingpowerplant (.com) and you will see that for 80k+ you can have a 4v per cylinder M70 engine. Personally now that I know it can be done I'd like to see if another machine shop can make it happen cheaper. I'm sure provided the engine and heads $500-$1000 in R & D shop at a BMW performance shop like vacmotorsports at $70-80/hr will go a long way. Furthermore, getting a group pricing on 3-5 4v conversions probably wouldn't hurt either. check out the racingpowerplant website and tell me what you guys think. Its time to bring the 6.0L 48V power to the little guy.

Happy driving and much love

Id rather put the 430 Stock horsepower 6.0 liter in there. even if its 20 grand, its got to be cheaper.


THink about it this way, perhaps iwth 20 customers, BMW its grand self may be convinced to drop us engines with harnesses. THe 6.0 is is superior in just about every way, except for the price.I bet with decent nonemission mods, 550 horses could be coaxed out of it without too much trouble. I have seen inside that motor. Pure sex

hi guys, interesting read this is.

My question is,
i know, theoretically, you can bolt some 4 valve head on.

The thing i don't understand is, what about the part where the exhaust and intake is? one side would be right on one bank but what about the other bank? can the exhaust and intake be reversed so to be compatible with a V12? and if so, what about the cam pulley which is rotated by the chain?

how are all these more easily understood? Is there a simpler way to understand the techniques that will be used to fit in the 4 valves head from the M50 or till the S54?

I would like to discuss this with my mechanic so he would understand that such conversions are possible.

Anyhow,
great to know there are people still messing with the M70.
I've got myself an M70 for my E34 from a 750i.

it is currently being worked on. the engine is in and the the exhaust manifold is being made to accomodate for my right hand drive E34.

i am waiting for the mechanics to do up the wiring part and would be facing some glitches with the ECU since i've bolted on a manual transmission with a custom made adaptor. i've heard things about the EMU being sensitive about stuff.

here are my updates:

November 13 2007

Got the Powerflex bushes!

http://euroasians.net/wp-content/imagescaler/a7bcfadd66ea0789d15774415b24e80e.jpg (http://euroasians.net/wp-content/uploads/2007/11/powerflex_bushes_e34-32.JPG)


Here are the pictures of the poweflexes for the E34 in a complete kit!. I ordered them through a Singapore dealer Hotwheels for a good deal. The package took like 2 weeks to arrive which isn’t too long. I am really happy with the way it is package. For some people, package makes a difference. They are boxed in various sized, semi-transparent packaging for different bush dimensions.


http://euroasians.net/wp-content/imagescaler/c80f458cec7aa3cda13a673034a3639e.jpg (http://euroasians.net/wp-content/uploads/2007/11/powerflex_bushes_e34-36.JPG)


Also in the package, Powerflex provided steel sleeves and plates to eliminate any need of re-using the worned out or warps parts that you get in older cars. Like in my case, the Rear-axle beam bushes has never been replaced in my hands for the last 7 years?, i’m guess it’s like 10-12 years old. Nevertheless, the new bushes will make a world of a difference in handling.


http://euroasians.net/wp-content/imagescaler/6862e7b0071b660567b6d8a0ddd7b972.jpg (http://euroasians.net/wp-content/uploads/2007/11/powerflex_bushes_e34-39.JPG)


Other stuff like the Powerflex grease is also included. So if you were to get new bushes, i’d recommend these. i think the whole kit came out to like $230+ GPB?


http://euroasians.net/wp-content/imagescaler/ac445fc0141ecca7630e44f44e91f77b.jpg (http://euroasians.net/wp-content/uploads/2007/11/powerflex_bushes_e34-54.JPG)


http://euroasians.net/wp-content/imagescaler/153bc84f3b7ff6616db3261bc36704e1.jpg (http://euroasians.net/wp-content/uploads/2007/11/powerflex_bushes_e34-40.JPG)



November 10

http://euroasians.net/wp-content/imagescaler/3c229512aadc272b6322166d26b5738b.jpg (http://euroasians.net/wp-content/uploads/2007/11/dsc_2154.JPG)


Some pictures of my painted intake manifolds. I chosed a red and black theme. If you got it, flaunt it. Which explains the red pipes, all 12 of them. The intake manifold are really special, they are 2 seperate interlocking pieces.
But what’s also interesting is, they are 2 exact same pieces, just reversed, and!, the right intake manifold will supply air to the left bank of the 6 cylinders and the right manifold to the left cylinder bank! There’s still some work left to be done.
I used a can of black truck bedliner spray to lay the base with a good and strong rough finish. Then i masked the plenums to do the red ribs with an enamel red spray can. I then removed the masking and topped it with a can of clear flat spray since i couldn’t find any flat enamel red.
The lighting was poor and yellow so the pictures don’t really do justice..


http://euroasians.net/wp-content/imagescaler/9e17879cc496693fda57c6c1b867c2b2.jpg (http://euroasians.net/wp-content/uploads/2007/11/dsc_2157.JPG)


I will sand the embossed parts of the black plenum when it’s ready to be put on. When everything is in, the red ribs will stand out like nothing else!
The next few updates will be my:
Custom exhaust manifolds
Electric radiator fan (either a used Mercedes one or a new aftermarket performance unit)
Radiator (i might get a new all-aluminium performance unit of just re-use my M20 radiator)
Other stuff i forgot to mentionCustom CF Head covers

http://euroasians.net/wp-content/imagescaler/f1264d02edc8acd0d95591bf7a68ca82.jpg (http://euroasians.net/wp-content/uploads/2007/11/dsc_2161.JPG)


The good guys at Duke Racing who’s in charge of the whole conversion applied their carbon fiber building and wrapping skills on my head covers. I opted for CF wrap-on on my head covers and full CF injector cover since it’s much more obvious being one of the highlights of the engine bay and the fact that it’ll be removed from time to time for maintenence purposes.


http://euroasians.net/wp-content/imagescaler/5532e0b08b5a4e73f57b636292d39bcf.jpg (http://euroasians.net/wp-content/uploads/2007/11/dsc_2162.JPG)


The CF head covers is a tedious job. It failed a couple of times. they’ve got the driver’s side cover perfect but will be re-doing the other side. The excess will be cut and several layers of clear coat will also need to be applied before the final product can go live.
As for the injector cover, they are still on it. I’ve taken a look at the mould for it and it’s perfect. The cover will be popping out from the mould really soon, so watch out!

I've also created a blog for my V12 project, so if you like, please go to EuroAsians.net
(http://www.euroasians.net/)




October 04 2007

It's me again

progress is slow,
we've just pulled the engine.
will be cleaning it up and probably swapping it in next week!

http://www.bmwclubmalaysia.com/tom/v12/october/1.jpg

http://www.bmwclubmalaysia.com/tom/v12/october/2.jpg

Please provide some ideas on how i should detail it? like what colour combos for the head covers and intake manifolds(s)

i've seen some with red covers and black intake which is pretty nice. but i'd like to see what you can contribute?

August 30 2007

Okay guys, I've just gotten myself a front cut of an E32 750i. An M70 5.0 V12 and all necessary harnesses to be exact. :D:D:D but unfortunately, it's an automatic like all of them 750i

sounds crazy huh

Enjoy this!

http://www.bmwclubmalaysia.com/tom/v12/august/v12_m70_e34_300807.JPG

Now,
I'd just like to know
If anyone here has ever done an E34 V12 conversion before or at least tried or has relevant articles on this?
Inputs on engine mounts
Harness/wiring input
Shortcuts
Any 750i or 850i owners know any common bugs or problems with the M70 V12 which always need to be looked at or replaced?
Transmission: Any known suitable manual transmissions?
From BMWs
From generic jap cars?
Differentials: currently. it's a 2:09.
Say i stick with the automatic, what kind of ratio should i use better accelaration, or if its good enough stock?LSD options? would the regular units from the E30 and E34 be useable?
What kind of Preps to the V12 before dropping it in?
Messing with the V12!!
Easy ones? Intake, Chipping, Exhaust, would any yield any performance gains?
If you have other inputs, please do share themAll help appreciated!

Thanks!
Tom

more pics

http://www.bmwclubmalaysia.com/tom/v12/august/v12_m70_e34_300807%20%282%29.JPG

What's in the picture above will replace what's below....... :D

http://www.bmwclubmalaysia.com/tom/v12/august/v12_m70_e34_300807%20%281%29.JPG

longest post in history


you re doing quite a conversion there, but to answer your original question, the other head has to be turned around backwards. A nightmare. then your V12 would be too wide to fit in the e34 bay


Just wait for a 6.0 liter. 438 bHP is amazing. And that engine has so many tuning and FI possibilities

Why not just build a TT motor? MUCH cheaper and more Hp per $$$$...........

Hey do you have any info on what Dinan did exactly to your car because Dinan themselves would not tell me anything?

Also nice pic change PumpedTSI

Why not just build a TT motor? MUCH cheaper and more Hp per $$$$...........

My eventual conclusion

I have a stock 750il engine I just brought and Im looking to mod it to get it to around 400hp, can someone reccommend or refer me to someone that could do this for me that is not too expensive Or could someone please tell me what would be needed to accomplish this(parts,etc.).

Thanks in advance.

Merc

IM sorry but its not going to happen. From flow numbers Ive seen you can do it with a little(all thats possible head work) , stepped custom headers, etc etc theres even cams but dont ever count on 400 HP.


I know it sounds insane, but its just damn near impossible.


350 to 360 is in your reach





Go FI

FI is the ONLY way to get those numbers to a decent level or a 6L conversion = $$$$

Id rather put the 430 Stock horsepower 6.0 liter in there. even if its 20 grand, its got to be cheaper.

THink about it this way, perhaps iwth 20 customers, BMW its grand self may be convinced to drop us engines with harnesses. THe 6.0 is is superior in just about every way, except for the price.I bet with decent nonemission mods, 550 horses could be coaxed out of it without too much trouble. I have seen inside that motor. Pure sex

Ummm!!! My 6L produces 455 HP and 503 ft-lbs of torque. The new 6L (N73) is a torqueless engine. I get more torque at the wheels at 3500 RPM than the N73 makes at the crank at peak.

FI is the ONLY way to get those numbers to a decent level or a 6L conversion = $$$$

Agreed. I'd get a stage III Dinan TT in a heartbeat. I wanted to get the Stage II on E-Bay but the guy was not very responsive. It would have been fun to take the Stage II and experiment to get it up to a Stage III level performance.

Ryan.....I am so envious of you. I am on the waiting list for Dave's dads Stage III if he ever sells it.

Can anyone tell me what I might need to do a 6L conversion? Or where can I get a decent priced 6L from?

Can anyone tell me what I might need to do a 6L conversion? Or where can I get a decent priced 6L from?

Decent price? I don't know. But my car's 6L conversion was done by PowerPlant Racing in NC, USA (http://www.racingpowerplant.com/bmw_m70.htm). Mine is a High Torque version of the Option C (Had to meet emission standards).

Agreed. I'd get a stage III Dinan TT in a heartbeat. I wanted to get the Stage II on E-Bay but the guy was not very responsive. It would have been fun to take the Stage II and experiment to get it up to a Stage III level performance.

Ryan.....I am so envious of you. I am on the waiting list for Dave's dads Stage III if he ever sells it.

Faisal, I dont mean to sound pretentious but my car feels "slow" to me now......its boostjunkieitis...........I've experienced it before with other FI cars. Of course, all it takes for a reality check is a quick stab on the throttle when being paced/tailed by a decently high Hp car and for him to be 2 football fields away in the rearview in a few seconds.........works wonders...

Im really looking to just add about 40 more hp. A friend of mines who is a electronics/engine genius makes a custom ecu for the M70 that will add about 70hp to the stock M70. He provides the ecu pre-mapped with all the sensors along with a custom stand alone wiring harness. He also told me I could use my original throttle bodies. The test engine that he used had 160,000 miles on it and it put out 369hp . So could anyone tell me what else I need to do to achieve the extra 40 to 50hp? Someone told me a shrick cam? What yall think?

One of the biggest problems for the M70 is that the head breathing sucks bigtime and its really hard to port with not much meat between the water jacket passages.........this is why FI is the best big Hp option........

Man speaks the truth. SHort turn radius is worse than a mopar 318


Ive thought about supercharger manifolds, but even with the twin screws, its not really addressing the m70 platforms issues. Its got loads if runner, mean flow velocity. It cannot feed itself much more air.

Turbos are its only hope

Hey guys I think you all don't give enough credit to head machining. Here is a picture to show you what I am talking about. The green is where the air pockets causing bad flow but if you machine off the blue area then it should flow a lot better even though the angle still sucks.

http://img216.imageshack.us/img216/2230/v12headcutaway069withmapt7.jpg (http://imageshack.us)

Yes that would require some very skilled work, which = $$$$$, but it should increase the power to 400 HP by itself. That may seem optimistic but it would be possible with the amount of displacement and if the heads flow as bad as you guys say they do.

Also someone else said in another thread that if that is done then the valves would have problems from losing that quarter of an inch of the guide. But they still will be held in place from the top of the guide that is under the cam and I think it would still work fine.

Hey guys I think you all don't give enough credit to head machining. Here is a picture to show you what I am talking about. The green is where the air pockets causing bad flow but if you machine off the blue area then it should flow a lot better even though the angle still sucks.

http://img216.imageshack.us/img216/2230/v12headcutaway069withmapt7.jpg (http://imageshack.us)

Yes that would require some very skilled work, which = $$$$$, but it should increase the power to 400 HP by itself. That may seem optimistic but it would be possible with the amount of displacement and if the heads flow as bad as you guys say they do.

Also someone else said in another thread that if that is done then the valves would have problems from losing that quarter of an inch of the guide. But they still will be held in place from the top of the guide that is under the cam and I think it would still work fine.


Its not as simple as the cross section makes it look.


The heads really really suck


they flow at less than 50% efficiency, even a 10 percent gain is difficult and that only increases max HP by a certain percent.


Count on 360 in a BMW


Ive seen reports of over 400 bhp but with , as you said, a lot of headwork, cams, intake work, aftermarket injection, and very, very nice headers.

With all the exhaust ineficiencies as high as they are, stepped tube tuned headers are vital


or you could turbo it

o you could do headwork and turbo it

or,


you could wait for the new damn 6.0 torquelss or not, that 760 is a damn beast.

Okay I don't mean to sound like a broken record so this is the last time I am going to say it: if you machined those heads right it would differently improve the power greatly.

Just in general though it is extremely hard to get 2 HP per cubic inch of displacement without FI. That is why I am really stumped that with all the work done to pumpedTSI's car that he is not making more power. (and not having to add a lot of octane boosters to his gas)

These are some of the cars that I could really see the headers curving more up then down to fit and the damn steering setup does not help with fitting good headers.

Also Ahmed303's car does not produce more torque then the 760 until after 3100 RPMs according to his sheet. 760 = 444 lb-ft @ 3900 RPM/ Ahmed303's car 443.4 lb-ft @ 3100 RPM

The 760 would be a good car to tune except you better have deep pockets because everything on it is so new that you would be redesigning a lot of things and even a 2003 with 40,000 miles on it would still be around $60K. You would have to deal with dual vanos, OBD2, and an even more crapped space with the bigger motor.

I just got news from a tuner who can rework the N73B60 motor to a 6.9L displacement. The cost however is not available at the moment as this is in R&D phase (Turbo implementation). Here are some initial details (I am salivating):

AXA - 6.9 liter
Power ratio 112 hp / liter
Bore 90
Stroke 90
Displacement 6871
Intake valve 36.0 / 5.92
Exhaust valve 30.5 / 5.90
Compression ratio 11.0 / 1
Int cams 284 dur
Exh cams 276 dur
NA HP 772 @ 7600
NA Torque 703 @ 5200
Turbo HP w/ 12psi approx 1,003
Turbo HP w/14psi approx 1,205

Also Ahmed303's car does not produce more torque then the 760 until after 3100 RPMs according to his sheet. 760 = 444 lb-ft @ 3900 RPM/ Ahmed303's car 443.4 lb-ft @ 3100 RPM.

I meant to say 3500 RPM (Not 2500).

Lets make sure everyone knows that the "N73" is the latest 6L V-12 from BMW it is NOT a derivation of the M70 series.

As to the suitability of this engine for extreme tuning? It will for sure be BIG $$$$$, it is more then just VANOS, the engine is set up with variable valve lift as well as timing, this engine has direct fuel injection, and all of the engine's electronics is tied very closely to the transmission and body electronics.

Just to give a look at the complexity of the head:
http://www.mwrench.com/Whitepapers/123-4.jpg

and engine:
http://www.mwrench.com/Whitepapers/123-1.jpg

If I were building a super car from scratch or a show queen, I might consider using this engine but for absolute HP/$ these engines just won't make it. It is fun to theorize about it and some tuners near BMW will have their versions of performance BMW V-12 engines but this is NOT for the masses. These will be "one-off" engines for the WOW factor and wow factor only.

I guess I am getting lazy (and cheap) in my old age, just so many easier ways of getting BIG power easily and cheaper then tackling a BMW V-12 project.

If I were building a super car from scratch or a show queen, I might consider using this engine but for absolute HP/$ these engines just won't make it. It is fun to theorize about it and some tuners near BMW will have their versions of performance BMW V-12 engines but this is NOT for the masses. These will be "one-off" engines for the WOW factor and wow factor only.

I guess I am getting lazy (and cheap) in my old age, just so many easier ways of getting BIG power easily and cheaper then tackling a BMW V-12 project.

I couldn't agree more. The cost of this is way too high (Talk about 6 figures). I agree that there are way cheaper and better ways to make more power.

Okay I don't mean to sound like a broken record so this is the last time I am going to say it: if you machined those heads right it would differently improve the power greatly.

Just in general though it is extremely hard to get 2 HP per cubic inch of displacement without FI. That is why I am really stumped that with all the work done to pumpedTSI's car that he is not making more power. (and not having to add a lot of octane boosters to his gas)

These are some of the cars that I could really see the headers curving more up then down to fit and the damn steering setup does not help with fitting good headers.

Also Ahmed303's car does not produce more torque then the 760 until after 3100 RPMs according to his sheet. 760 = 444 lb-ft @ 3900 RPM/ Ahmed303's car 443.4 lb-ft @ 3100 RPM

The 760 would be a good car to tune except you better have deep pockets because everything on it is so new that you would be redesigning a lot of things and even a 2003 with 40,000 miles on it would still be around $60K. You would have to deal with dual vanos, OBD2, and an even more crapped space with the bigger motor.

Jimmy,
I agree that my car "could" make more Hp IF certain criteria and conditions were improved/different/more efficient. Remember, this setup is based on 1992 technology and has not been modified from that format since then........I'm sure Dinan would do some things a little/lot differently if they had to undertake this project in 2007. I know that equal length headers would probably help however mine has the cast Dinan manifolds with a turbo hanging off the end of each one. This is why FI can overcome/overlook some flow inefficiencies and just take the "cave man" approach by forcing more air in.......gets the job done...

I plan porting some M70 heads, but i doubt I will get any flow numbers different than what has already been done


I disagree on the 6.0


Its scary looking because its new.


6 years from now, there will be a 1000 HP version of it

No one said that any power boosts on the BMW V12s are easy just I am like 323I Junkie where I love these motors. It makes sense for a 760's motor to be closely tied into the rest of the car to make a great car that is amazingly fast. As a matter of fact one killed my dad's V6 Miata on the way home from work tonight.

Just wondering has anyone heard of any major performance being made with the M73 5.4 Liter V12? It is the only V12 we have left out so far and I have only really seen The Transporter where a E38 750 had a manual to name anything done to that motor.

I am counting on two years to build mine.

And a lot of trips to either Roswell or perhaps we can get the flowbench in 08. Either way, I am not putting it in the trans am yet....I am going to build a live engine stand

wasnt the transporter a european 735/5 ?

You had to watch the director's commentary because he says that it was a custom one of a kind V12 and that there were no manual V12s at the time so they called it a 735. Also when he is going in reverse in the first chase sense the V12 is revving really high like 6K and screaming which is notorious for the V12.

Oooohhhhhhhhhh


Sick

Just wondering has anyone heard of any major performance being made with the M73 5.4 Liter V12?

The M73 is a warmed over M70, higher compression (M70 = 8.8:1) goes to 10:1 on the M73, Displacement from 4988cc to 5379cc. HP = 326

Major changes in M73 vs. M70 were redesigned exhaust port flange to accommodate a SS manifold for air injection, Redesigned crank snout, different vibration damper, electronics timing now comes from teeth around the flywheel instead of the damper.

The head was changed but not for the better, the cams use a MUCH SMALLER bearing journal and hollow camshafts with shrunk on sintered metal cam lobes, valve spring pressure has been reduced and roller finger followers were used. There are no performance cams available to my knowledge and M70/S70 cams will not work/fit. Exhaust ports were changed but only the clocking of the bolt locations, the port design is identical.

Some electronic tuning has been done on E31 M73 vehicles and one person has reported an approximate gain of 46 HP.

If performance stuff were available for the M73 it probably would respond much better then the M70 because of the bump in displacement and nice bump in C/R. C/R in the M70 at 8.8:1 explains a lot why it will not respond well to tuning upgrades and why it doesn't respond to port work.

HTH

So basically they changed the M73 so that it is even harder to tune than the M70 and it is sad that with a chip the smaller displacement V12 has the same or more amount of power.

C/R in the M70 at 8.8:1 explains a lot why it will not respond well to tuning upgrades and why it doesn't respond to port work.

HTH

It seems like the best upgrade for the M70 then would be pistons to raise the compression ratio. From E31.net it looks like the only major difference between the 850i and the B12 5.0 is the C/R (I'm sure there are more). Why isn't there a bigger push to get pistons?

It seems like the best upgrade for the M70 then would be pistons to raise the compression ratio. From E31.net it looks like the only major difference between the 850i and the B12 5.0 is the C/R (I'm sure there are more). Why isn't there a bigger push to get pistons?

They are expensive. For customs forged pistons from Wesbro you might as well hand them your first born.

Weisco forged pistons are only required if you go turbo or SC............otherwise hyperutectic pistons are perfect and great quality and cheap ($25-30 ea)..........I'm sure Keith Black (KB) might entertain making a few sets if asked.........

In order to replace pistons you have to have ferrous coated pistons to work in the Alusil bore, then you have to VERY carefully buff the bore to make sure the walls will seat the rings, it really requires a special lapping process which no one has available. Yes they are expensive and I don't think anyone besides Kolbenschmidt (sp?) makes this type of piston. I don't know if Wiseco's ceramic coated piston will work (it does work in the Nikasil V-8 block but not sure about compatibility in the V-12 Alusil block) and if it doesn't work it is an expensive experiment.

That is the point with this engine series, you just don't "replace" things for performance, This was BMW's first production engine using Alusil process. Hardened Cylinder walls are formed during casting process and requires the previously mentioned pistons. Ahmed303's engine has been bored out beyond the hardened wall area and a iron dry sleeve inserted, His engine uses Wiseco pistons, the entire process to raise the displacement and compression is a very expensive proposition and a bit risky, requires extreme precision boring and sleeve process. Due to the different expansion rates of aluminum and iron care has to be taken getting everything sized right or block distortion will result. Not enough room for a "wet sleeve" process.

Most HP claims are not measured on an engine dyno but calculated back from a chassis dyno. Driveline losses vary and are not constant. In many articles about chassis dynos even the manufacturers of chassis dynos state that estimating engine HP from a chassis dynio is exactly that, an estimate!

http://www.mwrench.com/Whitepapers/Dyno.pdf

Just a chip set on the M70 engine will not give it any more then 10-15 HP MAX! This is why I got excited when a guy in LV, who owns a M73 powered car reported ~306 HP at the wheels (up from ~260HP) but he also changed the exhaust system. The M73 DMEs can not be chipped, they have to be replaced by removing and resoldering a replacement chip, not a DIY unless you can handle precision u/circuit soldering.

It is cheaper to buy a Falconer V12 than build up an m70

I think they are about 20 Grand including Motec ECU, even at 30 grand I bet you would still pay off


Imagine an 850 with a a T-56 Viper Spec tranny and a 720 HP / 765 lb-ft engine that ran on street gas and did that

ALL MOTOR!


If you you are stuck on 5.0 liter displacement (This one is 600 CI, large I admit but still) Im am sure they could knock .25 inches off the stroke and bring it down to around 565 cubic inches or even less, the thing is small block chevy architecture and is pretty identical to 1.5 400 CI chevy small blocks. Meaning if you wanted a 4.125" bore and a 3" stroke it would be technically possible (This would be about 480 cubic inches and with same heads redline would be raised to around 7K RPMs)


lot of possibilities...you then have servicable, rediculously overpowered V12 850....that would put so many cars to shame...in stock configuration on the low performance edition, this engine makes 560 ft-lbs at 1500 rpms an 750 at 4500. You would not even notice a 750 or 850's porkiness

It's just sad that the CR holds it back. Sooooo low....

It's just sad that the CR holds it back. Sooooo low....


BUT GREAT for turbos...........

Dinan claims that with their M70 chip set you would get 326 HP instead of 300, which would differently be a crank measurement, and that is what the M73 gets stock.

Personally though if I were to turbo my car I would want to lower the compression down to 7.5:1 from 8.8:1 for more boost and theoretically a better power gain.

Yup, M73 was supposed to be 326 crank HP stock.

Jimmy, most turbo applications use an 8:1 ratio...........not sure if too many go much below that.........maybe 7.8:1.........

The most of the time you don't see below 8:1 CR because it can be difficult to compress higher octane fuel but 7.5:1 can still barely compress 93 octane gas.

how close does the piston come to the head at TDC? Could you replace the rods with longer ones to raise C/R?

You can not just arbitrarily change rods, If you go longer or shorter, you will have to change the position of the wrist pin in the piston (read new pistons, custom pistons).

To directly answer your question, the pistons on a M70 actually extend past the top of the block a few thousandths when at TDC the head gasket is thick enough to prevent the pistons from touching the heads.

No easy or inexpensive way to increase the C/R.

dang Ed..........BMW didnt leave the backyard tuner much to work with........

dang Ed..........BMW didnt leave the backyard tuner much to work with........


Yeah, ain't that the truth!! The M70/S70 did the job it was supposed to do quite well, big torque for a heavy touring coupe and sedan. Unfortunately BMW started with a basic design that was flawed (head design) and did not follow thru with any upgrades, it was in engineering but the marketing folks and maybe the bean counters were responsible for squashing performance migration for a BMW V-12. We all are taken in by the image or idea of a "V-12" which is associated with high reving, sweet sounds, and megapower!

http://www.mwrench.com/Whitepapers/V-12%20Myths/%20V-12%2048%20valve.jpg

Notice the last sentence!!


Even with the M60 engine, Great basic design, but, every few years they changed some design that would effect tuning efforts! First, M60 had a double row timing chain, then the M62 came out and had a single row timing chain and is not backward or forward compatible with the M60 engine, then they went to a single VANOS (M/Y '99) and the cam driving system was again changed. Cams are different from model to model and not interchangeable!

Alusil cylinders make piston changes a very complex issue.

Makes is very difficult for any tuner to spend time and money to develop low cost cams, high performance products when the target keeps changing. The volume isn't there. This area is only for "big buck" tuners with close ties to BMW.

As usual, this is MHO!

I take it you guys arent into the Falconer?

some updates from me :) i wonder if you guys are interested in these pieces.

November 29

Carbon Fiber M70 V12 Fuel Rail Cover

http://euroasians.net/wp-content/imagescaler/ebc09d08aba9239fe4b0d0d1e2e886bd.jpg (http://euroasians.net/wp-content/uploads/2007/11/carbon-fiber-bmw-m70-v12-fuel-rail-cover.JPG)

Finally, the moment of the week i’ve been waiting for! My CF fuel rail cover!. I’ve seen the mould and now, the final product straight from the vacuum bag! though it hasn’t been thoroughly cleansed, the
cover looks awesome.

every little detail is there. I especially like the raised epoxy BMW roundel and lines. Though it would better if it was more generic like totally flat or something like the 850csi’s but these are good enough for me.

http://euroasians.net/wp-content/imagescaler/ba82340dcba83cad5631d3a5786388c0.jpg (http://euroasians.net/wp-content/uploads/2007/11/carbon-fiber-bmw-m70-v12-fuel-rail-cover-3.JPG)

Duke Racing is again responsible for these CF parts. As you can see, there are 2 identical pieces from the mould with different weaves. the one on the left is made out of a 6K (6 thousand filaments/strands) carbon fiber material and the right from a 2K CF material.

Please bear in mind that the covers haven’t been prepared yet. They are awaiting a couple of layers of clear coat. If you are interested to buy these for your BMW M70 V12 engine for say your 750i or even your 850i, please let me know!

http://euroasians.net/wp-content/imagescaler/e08b4cdd92ce088f9469e66c017fb064.jpg (http://euroasians.net/wp-content/uploads/2007/11/carbon-fiber-bmw-m70-v12-fuel-rail-cover-1.JPG)

http://euroasians.net/wp-content/imagescaler/25e98c24d43a8dfbcbb0127edaf25186.jpg (http://euroasians.net/wp-content/uploads/2007/11/carbon-fiber-bmw-m70-v12-fuel-rail-cover-2.JPG)

How much?

supremebein:

thanks for the interest i will let you know asap!

http://www.youtube.com/watch?v=F3mg4Myx74Y

Here’s a video of my almost-complete project V12 E34. I now have manual throttle bodies instead of the drive-by-wire ones. I had problems with drive-by-wire throttles due to the absence of the stock automatic transmission and probably some other sensors which just seems too tedious to incorporate with my plans of fusing the V12 and M20 harness.

In the ECU compartment there are a total of 4 ECUs.

1. 1 for the drive-by-wire
2. 1 for the automatic transmission
3. 2 for each 6 cylinder banks

The motronic ECU is pretty much like an M20 ECU, just that the V12 has 2 of them for each bank.

Other updates includes the exhaust. Apparently my AC Schnitzer Exhaust system isn’t flow efficient for the V12. I have decided to use the middle section of the system instead.

Other stuff includes the intake elbows for the air filters later.

enjoy the video!

Holy shît! Now that is what I call "a lotta fun under the hood"!:buttrock

Cool! The throttle linkage looks very nice.

How much?Ditto!

You guys rock

thanks guys,

yeah the throttle links is pretty neat i must say compared to the drive by wires.

would like to ask u 850i guys something about your exhaust.
what kind of setup are you guys running (those who have a performance exhaust or something racy)
Do i just criss-cross the the pipes from the 2 banks to achieve a distinct V12 sound?

it's pretty mean sounding now like a high-pitched V8 with a noticeable burble.
but i want something more Ferrari.

Any tips for a V12 newbie? I want to do what people are doing to differentiate a V12 from a V something else.

Thanks!
Tom

Center resonator delete, 2.75" straight pipes to flat black powder-coated MAGNAFLOWS with stock 850 square tips. Sounds like a V12 should...

Has nothing to do with bmw but that`s a.... "nice" sound. http://www.youtube.com/watch?v=a2WYcwsDHU0&NR=1

Very nice, great throttle body linkages.

Center resonator delete, 2.75" straight pipes to flat black powder-coated MAGNAFLOWS with stock 850 square tips. Sounds like a V12 should...I bet it's real nice when it breaks down to first gear when approaching a Stop sign/Red light, Nice weight loss too!

Digging up the age old discussion about fitting Euro M3 heads to a V12 block. Consensus is that doing such a job basically involved redesigning the whole engine.

I found out about an interesting project in the US, a semi amateur designed a V8 using the bits and pieces from a Suzuki Hayabusa motorcycle engine, essentially making custom made crank and block to fit the stock internals and heads from the Suzuki motor.

One of the clever ideas he had to circumvent the problem of reversing one of the heads, he's actually running the two heads in opposite directions (with a chain drive at both ends of the block!), which not only makes the conversion possible but with the offset allows a shorter engine. See this picture for clarity: http://www.h1v8.com/albums/album_image/4566006/1357913.htm

I can't help thinking the same thing could be done using Euro M3 bits and pieces.. of course one of the cylinder banks would need custom cams since a V12 runs as two parallel inline sixes and reversing the heads as done on this V8 would cause one of the sides to have incorrect firing.

With the advent of high tech CNC machines, making custom blocks isn't as terrifyingly expensive as it used to be.

Thoughts?

http://www.h1v8.com/page/page/1562068.htm

Regards,
Bruckner

Now that is truly fascinating stuff. Thanks for posting that link.

Cheers

well, if you are going to grind left or right hand cams....why not just grind reverse cams and install the heads normally?

well, if you are going to grind left or right hand cams....why not just grind reverse cams and install the heads normally?

That won't work, heads on a V engine are not identical, one is the mirror image of the other. If you start off with two identical M3 heads, one must be flipped around (the passenger side bank, otherwise the intake/exhaust are on the wrong side). Then the cams must be redone because the two parallel sixes on a V12 run the same firing order, since you've reversed one of the heads you must in turn reverse the firing order of that head!

It's much simpler than the alternative solution of modifying one of the heads to reverse the location of the drive (so that both heads are driven by the same mechanism), the idea of having one drive at either ends of the motor (one for each head) is clever and allows the use of the heads as they are without substantial modification (only the cams need be changed).

This stuff would be much easier to explain with pictures..

Regards,
Bruckner

yeh thats right I forgot. We keep revisiting this topic every year. AS each year goes by, the 6.0 liter gets that much older...and more available.

323I Junkie, you should PM and ask Ahmed303 about the 6.9 liter conversion.

for the new V12 or the m73?

I just got news from a tuner who can rework the N73B60 motor to a 6.9L displacement. The cost however is not available at the moment as this is in R&D phase (Turbo implementation). Here are some initial details (I am salivating):

AXA - 6.9 liter
Power ratio 112 hp / liter
Bore 90
Stroke 90
Displacement 6871
Intake valve 36.0 / 5.92
Exhaust valve 30.5 / 5.90
Compression ratio 11.0 / 1
Int cams 284 dur
Exh cams 276 dur
NA HP 772 @ 7600
NA Torque 703 @ 5200
Turbo HP w/ 12psi approx 1,003
Turbo HP w/14psi approx 1,205

This one! Based on the N73 6.0 liter.

yeah that would dominate

Since I have purchased my M70 E36 I have put countless hours of research into bolt-on M70 upgrade options, and some even more extravagant options as well, more out of wishful thinking than actually having the mean$$$. Through my research I have read through this thread several times and see that it has been brought back from the dead a couple times so I don't feel too bad about bringing this one back to life yet again. I have also come across this.......

http://www.racingpowerplant.com/bmw_m70.htm (check out option F)

........I believe several posters on this thread are very familiar with this guy, but from the sound of things it looks he thinks he might have a workable 4 valve head option for the M70, I am assuming a custom built head by the price. Just thought I would pass this along and see what everybody thought about his M70 programs.

As for 6.1L conversions I found this a while back.
A german company.

Gives you 438hp and 620nm of torque.
Price unknown.

http://www.noellemotors.de/6_1l_Motor_Basis_BMW_M70_M73.117+M55ca4f2158b.0.ht ml

I decided to go F/I on my car.
Should be installed in June/July

I still might wind up putting one of these in my T/A. Ive full circle with the build of the SBC or LS1. Theres just no way in hell in that buying a 750 and gutting it will cost more than 3500 bucks.




On another note, does an M20 transmission bolt to an M70?

http://www.racingpowerplant.com/bmw_m70.htm (check out option F)

........I believe several posters on this thread are very familiar with this guy, but from the sound of things it looks he thinks he might have a workable 4 valve head option for the M70, I am assuming a custom built head by the price. Just thought I would pass this along and see what everybody thought about his M70 programs.

This is Henry Lawrence known for his work with sleeving M70 series to get 6.0L, multiple throttle bodied engines, etc. His 4 valve head has been on the drawing board for years but no one has put up the money that is needed to get the project off the ground. He has never built a set of heads to date!

There is a guy in the UK that does have a start on putting S54 heads on a M70 doing all of the machining work to encase the valve drive system etc, but it isn't running yet either and I have doubts about the viability of this project.

Yes the later V-12 (N73) has possibilities but, nothing on that engine will fit the M70 bottom end so it would be working with what ever is available for the N73. (not much!) Production numbers of the N73 engine are low so---who knows??

How much can you get a N73 for? Does anyone have measurements for that engine??

here are a set of heads for sale:

http://cgi.ebay.com/ebaymotors/Parts-Accessories_Car-Truck-Parts-Accessories__BMW-760-12-CYLINDER-HEADS_W0QQitemZ270351067430QQddnZPartsQ20Q26Q20Acc essoriesQQadiZ2865QQddiZ2811QQadnZCarQ20Q26Q20Truc kQ20PartsQ20Q26Q20AccessoriesQQcmdZViewItemQQptZMo tors_Car_Truck_Parts_Accessories?hash=item27035106 7430&_trksid=p4506.c0.m245&_trkparms=72%3A1171|65%3A12|39%3A1|240%3A1318

here are a set of heads for sale:

http://cgi.ebay.com/ebaymotors/Parts-Accessories_Car-Truck-Parts-Accessories__BMW-760-12-CYLINDER-HEADS_W0QQitemZ270351067430QQddnZPartsQ20Q26Q20Acc essoriesQQadiZ2865QQddiZ2811QQadnZCarQ20Q26Q20Truc kQ20PartsQ20Q26Q20AccessoriesQQcmdZViewItemQQptZMo tors_Car_Truck_Parts_Accessories?hash=item27035106 7430&_trksid=p4506.c0.m245&_trkparms=72%3A1171|65%3A12|39%3A1|240%3A1318 (http://rover.ebay.com/rover/1/711-53200-19255-0/1?campid=5335818596&toolid=10001&mpre=http%3A%2F%2Fcgi.ebay.com%2Febaymotors%2FPart s-Accessories_Car-Truck-Parts-Accessories__BMW-760-12-CYLINDER-HEADS_W0QQitemZ270351067430QQddnZPartsQ20Q26Q20Acc essoriesQQadiZ2865QQddiZ2811QQadnZCarQ20Q26Q20Truc kQ20PartsQ20Q26Q20AccessoriesQQcmdZViewItemQQptZMo tors_Car_Truck_Parts_Accessories%3Fhash%3Ditem2703 51067430%26amp%3B_trksid%3Dp4506.c0.m245%26amp%3B_ trkparms%3D72%253A1171%7C65%253A12%7C39%253A1%7C24 0%253A1318)

Now if only those would bolt right up to the M70 bottom end:(........ I would buy them now.

The cylinder bore centers of the M70 engine is 91mm.
The cylinder bore centers of the N73 engine is 98mm.