Turbo for s50b32 m3

blue arrow · Tweet this Post! #1 (**permalink**) 05-06-2007, 11:34 PM

Hi i need some advice on the most suitable turbo for an m3 with engine s50b32, dual vanos, comp 8.5:1, max rpm 8000. The car is going to be 50/50 street/strip. I have a gtk hp66(650), but doubt that choice now as i've been reading a lot in the forums. My target hp is 600whp. The max boost i want to run is 22-23psi.

Robert · Tweet this Post! #2 (**permalink**) 05-07-2007, 06:43 AM

Quote:

Originally Posted by blue arrow

Hi i need some advice on the most suitable turbo for an m3 with engine s50b32, dual vanos, comp 8.5:1, max rpm 8000. The car is going to be 50/50 street/strip. I have a gtk hp66(650), but doubt that choice now as i've been reading a lot in the forums. My target hp is 600whp. The max boost i want to run is 22-23psi.

a GT-K 500 or 550 would be a better choice I think.

blue arrow · Tweet this Post! #3 (**permalink**) 05-07-2007, 07:51 AM

The gtk500/550 is rated 550-600hp, my goal is 600whp-700+crankhp.
the s50b32 is eurospec motor-321hp stock, i don't want to tighten up at top end that is why i looked at the 650. any idea on spool rpm with these units

Robert · Tweet this Post! #4 (**permalink**) 05-07-2007, 08:19 AM

Quote:

Originally Posted by blue arrow

The gtk500/550 is rated 550-600hp, my goal is 600whp-700+crankhp.
the s50b32 is eurospec motor-321hp stock, i don't want to tighten up at top end that is why i looked at the 650. any idea on spool rpm with these units

Your setup is a bit of a unique one. The GT-K 650 in theory should work well albeit the spool up may be delayed slightly as it uses a T4 F1 P trim wheel. The only other combination I can think of that would get you to the same flow rate on the compressor and spool up like a GT-K 550 would be a T66 (HP66 compressor wheel) with a T3 F1 Stage V turbine wheel. The only thing I would worry about there is the top end backpressure on the smaller turbine section. In the end I think its going to have to be a trade off. For something like this the best thing I can recommend to make sure you get the exact turbo you need is to call the Support guys at Turbonetics. They can get with the engineers and come up with the absolute best set up for you. Try giving Ed, Steve, or Brian a call at 805-581-0333. They can spec out a turbo that will exactly meet your needs. Sorry I couldn't be more help.