Hey guys, I'm working on a little turbo project in my garage right now... and spec'ing out a turbo. Can anyone please recommend based on what they currently have?

I'm thinking T04 turbo with .81-.84 exhaust A/R (don't know which trim yet). I want such A/R so the car doesn't run out of breath at the top end... I want it to pulll hard to redline. In terms of compressor housing, it's everything between a T04E "57" Trim to T60-1.

My goal is to make about 400crank hp, but have a turbo sized to flow 500hp(MAX) efficiently, in case I ever want to go larger.

Can anyone, based on previous experience recommend inducer and exducer trims/diameters as well as A/R to do what I'd like.

Thanks a lot,

Boris

P.S. I think this is like my first post on this board... so... hello :).
P.S.S. I was told that this (http://www.activeautowerke.com/dyno/99MCoupe%20Turbo%20vs%2097M3.asp) is Omar's dyno on a T04E "57" turbo.. does anyone know ALL the specs of that turbo, or if I've been told wrong? Thanks a lot.

I'm sorry, I forgot to mention, this is on a '96 M3 (OBD-II, 3.2L).

You know AA uses a Mitsu TD06H 20G at 8.5psi = 398bhp right?

TD06 is a bit small, it's about the size of a T3 (in terms of exhausts). It's good for fast spoolup and mid range tq/hp, but it runs out of steam at 7k. Look at this power curve (http://www.activeautowerke.com/dyno/97M3%20Turbo%20vs%2097%20M3.asp). Note how fast it drops off at redline...

Anyway, all this still doesnt help me size a turbo... I'm DEFINIELY going with T04 turbine housing, nothing else..

Thanks,

Boris

Boris here is a dyno that I did last year Aug at 10.5psi and the power does not drop off.

This is with a 3.0" exhaust into the AA gen 1 muffler but will be replacing the AA this spring with a full 3.0" exhaust.

Actually, notice the torque curve drop off and the HP curve stay the same... that's a dropoff to me. Anyway, that turbo is pretty small. Compare your dyno to this: http://www.activeautowerke.com/dyno/99MCoupe%20Turbo%20vs%2097M3.asp

Anyway, I'm not really here to argue whether I should get a TD06 or a T04... I just need help sizing out the trim, compressor section, a/r, etc... I have a few turbo's in mind already, but I want to see what others will say so I can compare to my choices. C'mon... you guys must know this stuff..

Boris

Originally posted by ///3oris
Actually, notice the torque curve drop off and the HP curve stay the same... that's a dropoff to me. Anyway, that turbo is pretty small. Compare your dyno to this: http://www.activeautowerke.com/dyno/99MCoupe%20Turbo%20vs%2097M3.asp


The point of the turbo is to get you to the desired 300-450+ wheel HORSEPOWER faster (ie sooner in the rev range), so that you don't need 13k rpm to get there without it. How this happens is thru mega torque, which comes from a peak boost early in the rpm range. When the boost peaks, so does the torque. What you want with a turbo is for the the maximized boost to maintain HORSEPOWER---M3TurboCA's hp curve is right on the money! Although a little tad lean for my taste, that's one of the best street-turbo'd curves I've ever seen. Flat torque on a turbo car for like 2k rpm and then 350+whp from like 5000-7000rpm!

The bell-shaped curve of the TORQUE is the nature of the turbo.

If you want a flat TORQUE curve thru redline get a supercharger---in this case a flat TORQUE curve will give you a linearly increasing HORSEPOWER curve, it's just the way the mathematics works out (look at graph above and see what happens when torque goes flat--hp goes linearly up). but unless you're boosting more and more thru redline, that torque just has to start falling off on a turbo!

But you're not going to get a flat-thru-redline torque curve like that of a sc'r or normal aspiration with a turbo on your car--ain't gonna happen unless you get too big of a turbo that hasn't max boosted yet by the time you reach redline, and doesn't start boost til 6000rpm on a 3.2L (like a T88), but who wants something like that when you've only got 1000rpm to work with then?

Honestly, I don't agree, not 100%.... but that's not the point of this thread... I'm not going to argue what's best and not best... to _ME_ that turbo is undesirable. Also, don't forget, I want the turbo to flow up to 500hp (about 400-420rwhp) efficiently... I'm sorry, but that TD06 is too small for my application. And I still don't like what that torque curve looks like. I'd rather my turbo hit my max boost of say 10psi 500rpm higher, but work in a more efficient/cooler range. I'm not getting a turbo so I can have low-to-mid range torque/power... I want strictly mid-top end.

Another problem with that curve, is that as you drive it and keep shifting at redline, the car won't feel like it wants to pull harder, it'll feel like it's just "pulling." It's almost like comparing a OBD-I intake manifold and OBD-II intake manifold. The OBD-II doesn't flow as well, and if you've driven an M3 w/OBD-II manifold, you'll notice how at the top end, it pulls.... but it feels restricted... when with a OBD-I intake manifold, the low-mid range is sacraficed, yet at the top, it feels like the engine wants to keep revving. That's what I want. Turbo's are about compromises, but I'm not looking for a T-78 to make me 350-450rwhp.

Anyway, please stop with these types of posts... I seriously don't want to argue them, I just want oppinions on turbo sizes... forget the TD06, please.

Thank you,

Boris

Originally posted by ///3oris
And I still don't like what that torque curve looks like.

I'm curious: have you studied turbo graphs before? in this rev range (ie max 7000rpm)? Why don't you post a pic of a dyno graph you're shooting for...

Originally posted by ///3oris
I'd rather my turbo hit my max boost of say 10psi 500rpm higher, but work in a more efficient/cooler range. I'm not getting a turbo so I can have low-to-mid range torque/power... I want strictly mid-top end.

that's fine, but if you notice his M3 makes the power you want (~400bhp) from 5000rpm all the way thru redline. Let's say it was actually 420whp like you stated, but with the same curve...how could you not want 420whp from 5000-7000 rpm? You'd actually prefer to hit that same whp JUST at redline instead of all the way from 5000rpm? I'm talking horsepower here...if so, I just don't get it: you're asking for less torque and horsepower from 5000-6900rpm. Do you know how hp and torque is calculated?

Originally posted by ///3oris
Another problem with that curve, is that as you drive it and keep shifting at redline, the car won't feel like it wants to pull harder, it'll feel like it's just "pulling." [QUOTE]

of course not, it's already reached max boost! how can it keep pulling harder when it's not boosting any harder??? You've already reached maxed boost! :rolleyes: I'm beginning to think you've never driven a Turbo M3 now...no offense, but I'll bet you have not.

[QUOTE]Originally posted by ///3oris
it's almost like comparing a OBD-I intake manifold and OBD-II intake manifold. The OBD-II doesn't flow as well, and if you've driven an M3 w/OBD-II manifold, you'll notice how at the top end, it pulls.... but it feels restricted... when with a OBD-I intake manifold, the low-mid range is sacraficed, yet at the top, it feels like the engine wants to keep revving. That's what I want..

No, by what you're explaining, what you want is a supercharger. Have you driven an SC'd M3 yet? Please tell me you have, and don't lie, ;)

Originally posted by ///3oris
Turbo's are about compromises, but I'm not looking for a T-78 to make me 350-450rwhp.

No, but that's what you'll need to get you that flat torque curve in the top end--you'll need a turbo that hasn't hit it's dialed-in boost until you hit redline, which is way too big...Do you not understand this? and you're asking for proper turbo sizing...
See, a supercharger does just that! it hits peak boost at redline! Hence you get the flatter torque curve up top, and you're still streetable.
Originally posted by ///3oris
Anyway, please stop with these types of posts... I seriously don't want to argue them, I just want oppinions on turbo sizes... forget the TD06, please.

Thank you,

Boris

Sorry, but I don't want fellow bimmerheads that are reading these posts getting misinformed about being able to get a flat torque curve on a BMW M3 that revs to 7000rpm, with the turbos we can fit on these cars...

I don't mean this to bash/flame or anything like that. But you're talking as if you want a turbocharged M3 setup that puts out a supercharged torque curve, which doesn't make sense to me--you're asking for a curve that a turbo won't give an M3! :dunno

If you want to PM me, I'll try and relate to you any other things I've learned from this stuff in hopes that it will help you out a little. :wave:

I'm thinking T04 turbo with .81-.84 exhaust A/R (don't know which trim yet). I want such A/R so the car doesn't run out of breath at the top end... I want it to pulll hard to redline. In terms of compressor housing, it's everything between a T04E "57" Trim to T60-1.

I don't know... Even a T04 turbine w/ .81 AR + T04E .57 trim compressor sounds big for your powergoals. Like full spool at ~4.5-5k.

Most of my turbo sizing knowledge comes from Hondas, but that's a big-mama jama with the T04 turbine.

Why not a T04E .62-.64(forget what's available) compressor plus a T3 turbine with a higher AR. Should EASILY supply 500bhp, or 400-420rwhp and spool up around 3.5-4k RPM depending on boost. Maybe a T3 60-1 compressor if you're wanting even more efficiency.

I know you don't want to hear this, but that TD06 turbo's torque curve doesn't look all that bad. Really reminds me of most factory turbocharged cars(actually looks alot like a 3S-GTE 2.0L Turbo MR2 dyno, only w/ more torque all over and a quicker spool-up due to more displacement). Having a turbo spooling up at 5k RPM is not going to be fun on a car that redlines at 7k RPM. It's ok when your car revs up to 8-8.5k RPM though. :)


I would have to agree with you guys that you are looking at way too big of a turbo for the sake of efficiency. If you were running really low boost you might even run into compressor surge due to the size of that mofo.

Why don't you figure out the Mass Flow rate of a US spec S52 and then look at compressor maps based on your absolute pressure. PM me if you want help reading compressor maps, it's really easy once you learn.



Look into a T04E compressor + T3 turbine though. Should suit your powergoals easily and offer good spool up.

Ok, I'm sorry, but I withdraw everything I've said.... thanks for all the help... I'll have to look elsewhere.

Boris

Boris: Sounds like you want a racecar turbo setup. If you don't care about low to mid range torque (ie 99% of street driving compared to drag race driving) then you want a turbo used by drag racers.

Totally different ballgame.

MrBlonde: Can you please tell me what you use on your cars? And do you have Dyno pics?

Thanks,

Boris

Boris,
why don't you go out and drive a couple of SC'd M3s and some Turbo M3s.
It sounds like you're just out here thinking you know what you want, but you only want people people to tell you what you think you already know.

Some suggestions were given to you about compressors and housing and you just shut it down as if no one knows anything on this board.

I use 60-1 compressor wheel in a T04E housing with 60 a/r, with the TD06, if that helps any, and can make 400whp all day with that setup. There's other guys using T61s that can put out 450whp all day. BUt you better believe that once maximum boost is reached the torque will begin to drop shortly after--it's not increasing boost on they up to redline so it cannot sustain the same torque---this can't be that difficult to understand.

Why don't you read a turbo book like Corky Bell's MAXIMUM BOOST and learn a few things first, or at least go out and drive some forced-induct M3s and then decide which route to go. and if you don't see that and these other posts as trying to actually help you out, then you've got other issues...

Vader, I'm not suggesting that anyone on this board is stupid... what I'm suggesting, is that there is no way in hell I'm going to use a TD06 or T03 exhaust housing... I thought I made that clear with the first post...

As far as driving SC'd M3's, done that.... turbo'd m3's unfortunately no... but I've driven many other turbo'd cars such as RX-7's and Supra's.... I know it's not the same... but ohe well... there aren't any people around here that I know that have an AA turbo...

Regarding Corky Bell, yes, I have his book, and have read it... and for your information, Corky Bells own M3 turbo kit uses T04 turbo's... I wonder why?

Honestly, I'm not here to argue, I'm here to look for oppinions on T04 turbo's... not TD06 or T03's.... that's it.... it's not me, it's YOU that can't understand that...

Boris

When did I ever say you have to use the TD06?...I was only pointing out that curve we saw above (the shape of it) is similar to what you will see with ALL turbo M3s, even ones with a T04---you were so concerned with the torque drop, but it willdrop and you've got to accept that. That's all I was saying--wanted to make sure a turbo is really what you wanted, that's all. Not trying to bash/argue here.
Originally I said nothing about the TD06, and hey that's cool if you don't want to use it :cool:, I honestly never said that you should.
That torque will start to drop shortly after max boost, though, but don't worry because it still will be fun as heck! :D.

honestly I hope it works out for ya!!

I think Boris is saying "I've already got a T04 manifold"

Originally posted by ///3oris
Can anyone please recommend based on what they currently have?


:buttrock :buttrock :buttrock

that's a monster garage project -- fit it into the mini cooper!

so what's the size of that sucker and where is it going?

Originally posted by ///3oris
Can you please tell me what you use on your cars?

www.bavariacars.com.au look for the silver M Coupe and follow the links


And do you have Dyno pics?

http://www.bimmerforums.com/forum/showthread.php?s=&threadid=30535&perpage=50&pagenumber=2

See dyno sheet on Dyno Dynamics (not Dynojet) and timeslips.

Blah, I'm a spaz... I read Jim C's posts about tuning, etc.. and it really made me lose confidence in my project... I don't know much about the mechanic that I wanted to tune my car, but I do know he has a couple of M3's running, daily driven, etc... doing WELL over the power levels I desire (400hp).

I do know that he does his tuning because he has connections at a BMW dealer... does anyone know if a dealer actually has a computer or something to tune stock ECU?

I'm really bummed BTW... and am ready to order an AA supercharger tomorrow... this sucks... I don't even know what I want anymore!!!

Sanity check?!?!?! :)

Boris

OH MY F*G G*D!!! And now, as I'm ready to buy an AA turbo, I read Stimpee's thread about his twin screw setup.... and I HAD to look at this: http://www.fastlane.com.au/Custom_Shed/BoomerBeemer.htm

Wow... the marginal benefits are starting to decline as time progresses, I swear....

AHHHHHH..... why so many options?!? Where do I throw my money?

Lol, I'm going to try to talk to stimpee this week and find out some details on his kit... if not, then AA has a #4 CS person I guess... *shrug*

Oh.. BTW, I must mention, I've had less than 4hours of sleep in the past week or more... and am sick... so my brain is.... farting to say the least.....

BTW, thanks for all the PM's... very informative/helpful!!

Boris

I have a 97, let me know if you do it and what you think

kfort@ifort.net

Originally posted by ///3oris
OH MY F*G G*D!!! And now, as I'm ready to buy an AA turbo, I read Stimpee's thread about his twin screw setup.... and I HAD to look at this: http://www.fastlane.com.au/Custom_Shed/BoomerBeemer.htm

Wow... the marginal benefits are starting to decline as time progresses, I swear....

AHHHHHH..... why so many options?!? Where do I throw my money?

Lol, I'm going to try to talk to stimpee this week and find out some details on his kit... if not, then AA has a #4 CS person I guess... *shrug*

Oh.. BTW, I must mention, I've had less than 4hours of sleep in the past week or more... and am sick... so my brain is.... farting to say the least.....

BTW, thanks for all the PM's... very informative/helpful!!

Boris

just take your time my friend, this is a big investment and all have their advantages and disadvantages--that said, you should be happy with any of the setups as long as they're working properly. But continue doing your research and only buy when you're absolutely certain, :).

To confuse you even more between which setup to take, I just got back home from cruising around with the turbo M3 on a 400+whp setup and I can't stop grinning, :laugh (hadn't driven it for 8 days because I've been fartin' around in a borrowed Mini Cooper S--fun!)
just kidding I'm sure you'll be going the supercharger route, which rocks, too!!

Lol, you are right, I probably will go the supercharger route... but this is mainly because of the following:

1) reliable... never worry about it
2) I love the linear torque curve... perfect for when I track...
3) Price (it's more expensive than what I'd pay for my custom turbo kit... but MUCHO cheaper than a "reliable, proven" AA kit.... so not even a comparison

Main things I'm losing are torque at a lower RPM, full boost when switching gears (instead of falling down all the time), and, obviously, the amount of torque is.... MUCHHH less...

I figured ~285 RWHP is plenty for me... most people want 500hp, yet don't realize how much that actually is at times... some are just plain crazy... :)

I calculated that my car will be running mid-high (most likely high) 12's in 1/4mi with my street tires... which isn't all that fast for straight line... but that's not really the main reason I have my car...

I honestly think there's NOTHING better than a turbo.. and although could be very reliable (and is, if properly installed/tuned), I don't trust my software unless I go standalone... plus, all the above stuff that I mentioned... so I'm thinking AA SC...

Pretty much one of the only things that'll change my mind at this point, is if the price went up.... if it goes up to $5700, I'm not buying it... $4800 is reasonable, considering it's a BMW...

*shrug*

Boris

P.S. Sorry for the long ass post... :)
P.S.S. I still don't like the torque curve of that TD06... lol :biglaughb