Turbo setup?

[CJR926]

The E46 has s/c and turbo. Why has no one developed a turbo for the e9x yet? If anyone has a turbo setup on their e9x I\'d love to hear about it.

[Brucewonder]

cast vs. alum block. Ours is too weak

[turbo8765]

Originally Posted by Brucewonder

cast vs. alum block. Ours is too weak

Um... no

The S65 block is quite strong. Also, there are plenty of high horsepower turbo Al block cars.

Given the performance of the centrifugal kits on the S65, the motivation for a vendor to develop a turbo kit is not what it otherwise might be...

[Ateam]

I cannot say why people did turbo on the e46 but for both e46 and this e90, turbo does not make sense to me given you basically lose all the benefits of the great NA engine in throttle response, no lag etc. Atleast a supercharger maintains the same feel as NA with no lag and instant response so that makes much more sense to me.

I guess a turbo might be a little more efficient but obviously people doing a mod like that could care less.

I am sure the s65 is much more complicating from a tuning perspective in order to program for turbos but thats just a guess. Maybe one will come down the line!

Also not a whole lot of room under the hood so maybe supercharger can be packed in tighter

[piloto]

You don't have much roof if any for a turbo in this engine. The fact that it's a V configuration and that it has traditionally located headers (unlike the F10 M5), there's practically no room to get e proper turbo setup. The inline configuration of the E46 was a bit more accessible for a turbo.

[IND-Distribution]

Although there are many challenges to developing a bolt-in turbo setup for the S65 engine, I'd say the biggest hurdle is plumbing. Because the engine is a V8, you'd have to first decide if you're using one large turbo or two small ones.

If you're using one large turbo, you'll have to have the exhaust headers connect at some point, join to a single pipe, and then run that pipe into the engine bay to connect with the exhaust side of a turbo (assuming you're not using a rear mounted system). There is not much space to run piping like this, let alone mount a turbocharger to boot.

If you use two small turbos, you have to create exhaust manifolds that fit inside the engine bay, and also again bolt to the exhaust side of a turbo.

From there, you'll have to run piping from the turbo out to a charge cooler, then back to the intake manifold. You'll need some kind of a down pipe coming from the turbo to an exhaust system.

The tight but efficient packaging of the E9x M3 just doesn't seem suited to a turbo setup. The reason a supercharger is possible from this perspective is because you can remove the very large factory air filter box, and place a belt driven supercharger in it's place.

Here are a couple of photos of twin and single turbo plumbing setups on another V-configuration engine, Nissan's VQ35, to give you an idea of what's involved in plumbing such a system:

Twin turbo:



(The turbos and down pipes are coated in a red high temp coating, you can see the passenger side turbocharger on the other side of the motor.)

Single turbo:




You can see how the plumbing can be very complex.

[CJR926]

Yeah I never really thought of space being an issue. I've seen v8 setups where the turbo is between the block and radiator but the plumbing is insane. Since the next m3 is supposedly going to be turbo, I can't wait to see what HPF is going to do with it!

[IND-Distribution]

I'm looking forward to the new turbo M as well.

[alpine335i]

Someone will Turbo the E9x eventually

[IFX]

Originally Posted by turbo8765

Um... no

The S65 block is quite strong. Also, there are plenty of high horsepower turbo Al block cars.

Given the performance of the centrifugal kits on the S65, the motivation for a vendor to develop a turbo kit is not what it otherwise might be...

We're not talking about any AL block cars, we're talking specifically the s65.

I haven't seen any s65 that has 900hp yet? (Flame suit on) Alot of HPF's are up there with the s54..

[alpine335i]

Originally Posted by IFX

We're not talking about any AL block cars, we're talking specifically the s65.

I haven't seen any s65 that has 900hp yet? (Flame suit on) Alot of HPF's are up there with the s54..

Don't you know forum members here have flame suit penetrating flames?

[Soorena]

I'm going to take this a bit OT. Why it's always Centrifugal? why not positive displacement? I would pick a whipple over any Vortech in a sec.

Originally Posted by IFX

I haven't seen any s65 that has 900hp yet? (Flame suit on) Alot of HPF's are up there with the s54..

in higher PSI's the S54 block holds better. However, the comparison you made isn't right. fair comparison would be built S54 vs built S65 not built S54 vs stock S65.

Originally Posted by Ateam

instant response so that makes much more sense to me.

Not actually. Centrifugal's response isn't much better than quick spooling turbos.

[pbonsalb]

Originally Posted by Soorena

I'm going to take this a bit OT. Why it's always Centrifugal? why not positive displacement? I would pick a whipple over any Vortech in a sec.



in higher PSI's the S54 block holds better. However, the comparison you made isn't right. fair comparison would be built S54 vs built S65 not built S54 vs stock S65.



Not actually. Centrifugal's response isn't much better than quick spooling turbos.

Centrifugal is often cheaper and simpler than a turbo. The boost curve is very relaxed, with very little midrange boost, so it is not as likely to blow up a high compression motor.

With a turbo, boost must be lower since it will all be there at the torque peak and cause detonation on the high compression motor. Higher octane gas helps, which is why the higher boost HPF cars use meth injection or lowered compression on the E46M3.

A centrifugal has a far worse boost curve than just about any turbo. With a centrifugal, you are looking at the square root of peak boost at half peak rpm. So 9 psi at 8000 rpm means 3 psi at 4000 rpm. With a turbo, you will have 9 psi at 4000 rpm and the centrifugal car will be left in the dust. It is only when the centrifugal really gets going, at high rpm, that the gap between the turbo and supercharger can disappear. Study the dynos of the same car in turbo and centrifugal form and you will notice dramatically more power under the curve with the turbo than with the centrifugal. I have done this with my E36M3, which I first centrifugally supercharged and then turbocharged. Torque is lots of fun. The turbo has it and the centrifugal does not.

Twinscrew or positive displacement superchargers are great. Car makers use them just like they use turbos, but no car makers use centrifugal superchargers. A twinscrew will make boost sooner than most turbos, except for maybe small twin turbochargers like on the N54 used in the older 135/335/535 or the small twinscroll single turbocharger used on the N55 in the newer 135/335/535. Both those engines make full boost at something like 1200 to 1500 rpm, which is incredible. A twinscrew is also incredible in that it produces boost early also, but since it is belt driven and dragging off the crank, twinscrew torque is usually much less than turbo torque on the same engine.

Twinscrews are harder to package. The have been run on E36M3s and on E46 325/330i and on E39 525/530i. All those cars have single throttle bodys with intake manifolds. There probably is not space to run one on an individual throttle body car like the E46M3 or E9xM3. It is also unfortunate that we have not seen one for the V8s like the E39 540i and later 5 series. Maybe eventually.

I have not really studied the E9xM3 to determine the space available for a turbo or two turbos. I would not run turbos without lowering the compression ratio unless I could get E85 gas. Even the newest direct injection cars that run fairly high compression like the 135/335/535 and the X5M, X6M and new M5 are still only in the 10.0:1 range when turbocharged versus the 12.0:1 of the E9xM3.

[IMG]

Originally Posted by alpine335i

Someone will Turbo the E9x eventually

Are you the guy I heard about doing the turbo project...trying to get PG's FI cam design from RD Sport? It would be nice to put a screen name on the project.

[alpine335i]

Originally Posted by img

Are you the guy I heard about doing the turbo project...trying to get PG's FI cam design from RD Sport? It would be nice to put a screen name on the project.

No not me.

[newbieguy]

I've read/seen at least 2 german tuners did this turbo setup already. I recall the name of the company called Manhart and Emotion wheels showhorn the engine from the x5m/x6m into the E92 M3. I wonder how much $$$ that project costs.

[mshab356]

Originally Posted by newbieguy

I've read/seen at least 2 german tuners did this turbo setup already. I recall the name of the company called Manhart and Emotion wheels showhorn the engine from the x5m/x6m into the E92 M3. I wonder how much $$$ that project costs.

That's not turboing an S65. But how the hell did Manhart fit the X5/6M motor in that E92 M3?

[newbieguy]

Your right my bad its not turboing an S65 existing engine rather a transplant of a turbo engine. Not sure how they did it but they've done it. Here is the info. I found:

http://www.m3post.com/forums/showthread.php?t=427773

Originally Posted by mshab356

That's not turboing an S65. But how the hell did Manhart fit the X5/6M motor in that E92 M3?

[IMG]

Originally Posted by alpine335i

No not me.

[Tony135]

I turboed E9x m3 would be so win. I'd love to see one of those.

[CJR926]

http://www.m3post.com/forums/showthread.php?t=628602

Looks like we'll see a turbo setup sooner than expected!

[piloto]

I don't get the "let's turbo the S65" thought process. I'm not talking about the need for more power. That I understand. But given the limited room inside the engine bay, it's going to be a very compromised turbo setup, with lag far from the ideal. The S63 setup makes much more sense.