740i to M7 transformation - S62 swap

[blackknight530i]

******UPDATED 6/18/2014******

I just wanted to let anyone who's new to this thread know in the beginning that this swap is complete and working beautifully and it is completely understood now what needs to be done for people wanting to do this in the future. All issues have been addressed and the only thing that can't be dealt with (which is true of just about any engine swap to a different chassis) is that EWS was disabled and the VIN# in the DME is not matched to the rest of the car. Those are the only things that make it not a factory swap. The only codes that I get are from my old cats and old crank position sensor that I used and probably need replacing, but neither affect the drivability of the car. Again, these things could easily be addressed by buying new ones or better used ones. My car started with 190k miles, so what I've been adding to this thread lately has pretty much just been getting the rest of the car to a much nicer condition. One of these days when I get a bunch of time, I will go through all of my receipts and wiring diagrams and put together a proper parts list and required wiring changes as well as some diagrams to make a few of the custom parts needed. There are only about 5 parts on the entire build that were truly custom and non-BMW or modified BMW parts. Nearly everything used BMW parts for either the M5 or 750il or in some cases could have used them, but since I was still, learning were custom.

Anyways, here's how she looks currently:










******Original Thread******

Hey guys, I haven’t posted on the forums that much, but I have definitely been an avid reader and searcher. These boards have helped me so much over the last few years since I bought my first BMW and then my second, third and even my parents’ first.

Anyways, I wanted to let you guys now about the transformation that is currently underway on my recently purchased 2001 740i non-sport. I’ve been doing research on this project for about 6 months or so before deciding to pull the trigger on it and while some people will understand why I wanted to, others will surely claim that it wasn’t worth the money. I’ll put it this way, yes it is quite expensive, but I could have gone out and spent 3-4 times as much for a new 3 or 5 series and not been nearly as happy. So I say that with my daily driver ’03 530i sport and my ’01 ///M7, I won’t need a new car for a very long time.


20131003_171701 by blackknighti30, on Flickr

I was wanting to wait until I had the project completed before posting, because I know how these usually start. People say, “Can an S62 swap in an e38 work?” or, “How much will it cost?” or they even say, “This is going to happen” and it never pans out, so I wanted to tell people after it was done. Now that I’m at least half-way complete on this project and don’t have any intentions of backing out since I can’t exactly put the old engine back in, I figured I’d go ahead and share.

The car started out as a 2001 740i non-sport with 189k miles and bad timing chain guides. The engine runs, but I didn’t want it to jump time so I never really got it up more than about 35 mph while moving it from the transporter to my house. The transmission shifted well and it rode nice and smooth. It’s a pretty clean car that had records for the last 90k miles from the previous owner.


20131004_082419 by blackknighti30, on Flickr


20131004_082434 by blackknighti30, on Flickr

The engine came from a member on M5board.com who’s M5 had an unfortunate encounter with a guard rail while stretching its legs. The engine was an assembly line motor from 2003 that he had installed 42k miles ago and should be a great motor for my swap. It had absolutely no leaks and only a couple pulleys and the fan clutch/fan were damaged from the radiator pressing into them. It also had a new clutch installed only 300 miles ago. The engine also came still attached to the subframe and included the steering box, which we are hopefully going to be able to swap over.

Now on to the actual build.

First things first, we needed to pull out the old engine and transmission. We decided to disconnect all the hoses, wires, etc. and lift the car off of the subframe with the engine/transmission still attached. This was a little complicated as it was difficult getting the steering column disconnected from the steering box due to access issues, but we were successful.

20131205_075659 by blackknighti30, on Flickr


20131205_075626 by blackknighti30, on Flickr


20131205_075618 by blackknighti30, on Flickr

Here’s the now cleared engine bay and transmission tunnel:

20131205_075646 by blackknighti30, on Flickr


20131205_075634 by blackknighti30, on Flickr

Out with the old… In with the New:


20131206_180018 by blackknighti30, on Flickr

After we got the subframe out, we separated the engine and transmission from it and put the engine on the rack. We reattached the subframe and rolled the car out to do some pressure washing of the engine bay. It took three applications of purple power to get all the oil that had covered the bay, but eventually it was almost new.
We then began considering the possibility of swapping the steering box from the M5 into the 740i. We thought about swapping the M5 subframe first as it would already have the correct mounting brackets for the M5 steering box, but we found out that it had been slightly tweaked during its run in with the guard rail. We also noticed that many of the brackets that hold other various things, were in the wrong places or too short/long, so we decided that we are going to go back to the e38 subframe and just modify the brackets to the steering box. This is where we left off before this coming weekend when we attempt this.

Back to the engine…

The other thing we noticed was that the exhaust is a little bit different. Since I’m working with a M62TU exhaust system that only has two pipes going to the headers rather than the four that the M62 has, we need to figure out a way to make the S62 headers collect into the M62TU exhaust. One option considered was to use the M62TU headers with pre-cats on the S62, but this seems like a restriction that should be avoided. Another option is to find a M62 version exhaust system and install it directly to the S62 headers. This is also counterproductive since the M62 exhaust was much more restrictive leaving the cats than the M62TU exhaust. The solution I’ve come to now, but haven’t done yet, is to take the collectors from the M62 exhaust before the main cats and weld them onto the M62TU exhaust. This would keep the larger exhaust sections of the M62TU while removing the pre-cats from the system. Ideally I would have liked to have found the cat sections from an M5 and adapted those since the cats are much larger, but that will have to wait a while (I did mention this is an expensive swap, didn’t I?). The rest of the exhaust for now will be the stock M62TU until I figure out what to do in the future.

I also needed to install a new fuel pump since the M5 requires 72.5psi or 5 bar rather than the paltry 48psi for the M62TU. I bought a Walbro 255lph pump and swapped it over. This was pretty straightforward. I will also be installing a new M5 fuel filter and pressure regulator.

In regards to the pedals, I had bought a pedal set that ended up being for a pre-facelift 5-series rather than a post-facelift and therefore, there were a few differences in where the positions switches and clutch master cylinder are located compared to the facelift pedal set in the 740i. We needed to cut the brake pedal down to the size of the manual one and it worked. I just need to install the new clutch master cylinder and it should be ready to put back in the car.
The shifter arm, which is unavailable from BMW anymore, is made up from two broken 5-series parts welded together in order to extend it. I was able to order the selector rod, but it’s been a few weeks now and BMW still doesn’t know an ETA of when it will arrive, so we improvised and had the 540i selector rod extended as well. Both the arm and the selector rod needed to be extended 15mm. If I ever receive the part from BMW, I can swap it out, but honestly, I’m not sure it needs to be. The shifter itself is the one from the e60 545i and has a new shift boot and ZHP knob.

The “sport” button from the M5 will be installed in the console as well. This should be pretty simple since it is just two wires that need to be run from the console to the E-box. Also, since the servotronic steering control is actually handled by the DME on the M5 rather than the GM on the 740i, it should just be a matter of swapping which connecter in the driver side wheel well it goes to. They use the same type of barrel plug.
Speaking of wiring, I’m still working on this, but most of it should not need to be changed if you are using a facelift e38. I did however find that the fuel pump relay wire is on a different connector in the e38 than it is on the M5. The easiest way I found to connect it is to remove it from the module it is in and swap it over to the correct pin on the M5 module connector. The other option is to splice a round connector pin and place it in the white engine plug in the place where the M5 expects it. I will also need to run a wire from the clutch pedal position switch to the DME, but that should be pretty easy. Almost every other sensor wire and such (save for a few I haven’t messed with yet) are attached to the main engine harness including the reverse switch and gear position switch on the transmission and all other sensors mounted on the engine, so it is fairly plug and play.
Instrument cluster will be from an M5, but I am still waiting on my M35080 programmer so I can get the mileage corrected.

Motor mounts will need to be swapped with either M5 or 750iL mounts (they’re the same) as they are stiffer than the 740i/540i mounts.
Driveshaft is at Carolina Driveline in Spartanburg, SC getting extended and should be done next week or so.

I hope to have the engine and transmission installed by this weekend, but I won’t be able to have the car running until after the holidays. I’ll update the thread as I go along from now on. Pictures will likely be added to the appropriate places in the post as well.

Additional pictures: http://www.flickr.com/photos/98990094@N07/sets/72157638547102216/

This buildlog is also on M5Board.com: http://www.m5board.com/vbulletin/e39...-underway.html

[SEVEN40iL]

Nice work!

Would love to see the end result!

[dazednkenfused]

subscribed

[burninator]

I am excited to see this (as I usually am with these threads). I plan to embark on a similar journey some time next year and the more threads on the subject, the better.

[blackknight530i]

I am excited to see this (as I usually am with these threads). I plan to embark on a similar journey some time next year and the more threads on the subject, the better.

I totally agree. I can't tell you how many threads I've gone through in my research to get to this point. I plan on posting all of the relevant ones in the thread when it is completed.

[sigtwenty]

Jealousy level 87

[bruinbro]

Cool. Nice pics!

Electronics?

[zeeth2800]

subscribed.
very cool car you will have once it is all over.

[blackknight530i]

Cool. Nice pics!

Electronics?

The electronics will be worked on once the engine is in. Hopefully this weekend.

[franco90]

GOOD GOD , good times

[kulgan]

Sweet. Lots more pics please.
I'll be watching this with interest..
Nice to see a plan coming together.. Good luck and have fun..

[blackknight530i]

So, I know I'm getting a bit ahead of myself since it's not complete yet, but I know that based on all the research and parts finding I've done in preparation of this, I'm considering selling a parts list and diy once completed. What do you all think of that? Most of the information is already publicly available, but nothing is consolidated. If I put one together, it wouldn't be too expensive, but would help me recover some of the costs put into this swap. I haven't decided on this yet, but it's just an idea I was kicking around and I was hoping to find out if people would be interested in it or not. My mechanic friend and I are considering doing these swaps for others as well, so that is another thing I'm gauging interest for.

Let me know what you guys think. I realize that everyone wants stuff for free, but be honest guys, what's it worth to you?

[purplecty]

Sweet jesus!

[burninator]

So, I know I'm getting a bit ahead of myself since it's not complete yet, but I know that based on all the research and parts finding I've done in preparation of this, I'm considering selling a parts list and diy once completed. What do you all think of that? Most of the information is already publicly available, but nothing is consolidated. If I put one together, it wouldn't be too expensive, but would help me recover some of the costs put into this swap. I haven't decided on this yet, but it's just an idea I was kicking around and I was hoping to find out if people would be interested in it or not. My mechanic friend and I are considering doing these swaps for others as well, so that is another thing I'm gauging interest for.

Let me know what you guys think. I realize that everyone wants stuff for free, but be honest guys, what's it worth to you?

I would definitely be interested in a parts list. I'd say it'd be worth $50 to me.

[sigtwenty]

So, I know I'm getting a bit ahead of myself since it's not complete yet, but I know that based on all the research and parts finding I've done in preparation of this, I'm considering selling a parts list and diy once completed. What do you all think of that? Most of the information is already publicly available, but nothing is consolidated. If I put one together, it wouldn't be too expensive, but would help me recover some of the costs put into this swap. I haven't decided on this yet, but it's just an idea I was kicking around and I was hoping to find out if people would be interested in it or not. My mechanic friend and I are considering doing these swaps for others as well, so that is another thing I'm gauging interest for.

Let me know what you guys think. I realize that everyone wants stuff for free, but be honest guys, what's it worth to you?

Done right....id say sell em for a few bucks. 25 to 50.

Curious tho, can these s62 motors be mated to an automatic or no

[blackknight530i]

The problem with mating it to an auto is that the DME doesn't have a clue what to do with the auto computer. It has been done though with an e31 850ci. They connected the ZF 5HP30 to it, but it wasn't pretty and shouldn't really have been done. Now if you could make a standalone computer for the SMG version of the S6S420G and mount it up, you'd be able to use the steptronic shifter and paddles and it would make the rest of the swap much easier as you wouldn't have to source "no longer available" parts from Germany, but good luck.

[007008]

Good job, you are pretty much on par with what I have researched.
I just gotta sell this darn motorcycle and then find a m5.

[Alpina7]

love love love it!!! keep up the good work.

[blackknight530i]

007008, let me know when you do get one and if you want help.

[sigtwenty]

The problem with mating it to an auto is that the DME doesn't have a clue what to do with the auto computer. It has been done though with an e31 850ci. They connected the ZF 5HP30 to it, but it wasn't pretty and shouldn't really have been done. Now if you could make a standalone computer for the SMG version of the S6S420G and mount it up, you'd be able to use the steptronic shifter and paddles and it would make the rest of the swap much easier as you wouldn't have to source "no longer available" parts from Germany, but good luck.

Interesting. My issue is I dont know how to drive a manual transmission

[blackknight530i]

Interesting. My issue is I dont know how to drive a manual transmission

Ah come on, it's not that hard to learn and you will be extremely rewarded by doing so.

[xboss]

Interesting. My issue is I dont know how to drive a manual transmission

It's pretty easy. Heck, I bought an old Porsche when I Was 18 and only had about 15 minutes practice on my friends stick and I drove it away.

[franco90]

It's pretty easy. Heck, I bought an old Porsche when I Was 18 and only had about 15 minutes practice on my friends stick and I drove it away.

Same here 1 hour

Sent from my iPhone using BF.com

[M I C H A E L]

Interesting. My issue is I dont know how to drive a manual transmission

Learn its easy and what fun would they be as automatic. They were only made standard.

[burninator]

Interesting. My issue is I dont know how to drive a manual transmission

srs?