SMG II and Turbo on E46 M3

[nycM3]

Hey all,

quickie question here, lets say you have a SMG II gearbox, and wanted to add a turbo, would that affect anything? Would it mess the computer up cause it has more HP or Torque now or anything? Does anyone have this config with their E46 M3s? just wondering..!! thx

[RichP]

Obviously I have neither..but I think the answer would be yes and no. If the engine revved the same, then the SMG, in its manual modes, should be ok ,as it is the same as the standard 6-speed. However, that clutch would not last long with all that power(as is true in the E36) If you changed it to something stronger, its new grabbing and engagement problems may be an issue. You would really need a BMW tech to tell you know the car senses things such as slippage, engagement, etc; if it adapts in real time, or just runs a set program.

[Keith 95 M3]

Turbo?

On an E*46* M3?

No.

Not with that 11.0:1 compression ratio, you won't.

If you want to add a turbo, you have to do deep engine work if you want it to be reliable. You'd at least have to replace the pistons with something that could bring it down to at least 9.0:1, and I don't know if you can do that without the wristpin cutting into the oil ring groove. If you have to do that, you'll burn oil like a mofo. And if the wristpins can't be moved up in the piston any higher up the skirt (heh - he said "up the skirt"!), then you'd have to go with a shorter throw crank/rods since I doubt you could flycut the pistons to lower compression.

I mean, there is a reason Dinan and RMS, et. al., have yet to come out with a forced incudtion kit, and that's because it's not going to be cheap or easy.
-keith

[HDK]

Originally posted by Keith 95 M3
Turbo?

On an E*46* M3?

No.

Not with that 11.0:1 compression ratio, you won't.

If you want to add a turbo, you have to do deep engine work if you want it to be reliable. You'd at least have to replace the pistons with something that could bring it down to at least 9.0:1, and I don't know if you can do that without the wristpin cutting into the oil ring groove. If you have to do that, you'll burn oil like a mofo. And if the wristpins can't be moved up in the piston any higher up the skirt (heh - he said "up the skirt"!), then you'd have to go with a shorter throw crank/rods since I doubt you could flycut the pistons to lower compression.

I mean, there is a reason Dinan and RMS, et. al., have yet to come out with a forced incudtion kit, and that's because it's not going to be cheap or easy.
-keith

I spoke with a gentleman from RMS at the LA Auto Show...he said the supercharger kit for the E46 M3 is due out in about 5 weeks. The number to watch out for is @ 435hp....

[Ryan]

Originally posted by HDK


I spoke with a gentleman from RMS at the LA Auto Show...he said the supercharger kit for the E46 M3 is due out in about 5 weeks. The number to watch out for is @ 435hp....

435 thats awesome. Throw an exaust, Air intake, chip...

[nycM3]

so no one here now has a turbo on a E46 M3 then? =( hmm just wondering anyways, thx fer the input.

[Ryan]

Originally posted by nycM3
so no one here now has a turbo on a E46 M3 then? =( hmm just wondering anyways, thx fer the input.

I dont think there is even a S/C kit out yet. but soon

[HDK]

Originally posted by nycM3
so no one here now has a turbo on a E46 M3 then? =( hmm just wondering anyways, thx fer the input.

btw, I forgot to mention, the E46 M3 (stock) RMS had on display was one with the SMGII. SO, I am assuming the blower is designed to work with that transmission as well.

[Shane]

Turbo?

On an E*46* M3?

No.

Not with that 11.0:1 compression ratio, you won't.

There are turbo kits for the Integra Type R, and that thing has 11.1:1 compression. I have to wonder about its reliability, but if you really wanted to, you could put a turbo on anything.