here is a thing, with a 328, many people think that its a extreamly good engine to put tons of power on it, but this is wrong, i personally own a 328 and trust me its great, but the max u could go with it is about 310-350 bhp,
of cause there are big turbo kits out there, but the gear box will not take it, plus that engine is somehow bolted to the chases not in as good as the m3's where there is a some cradle thingi to support the engine, once the power is up and high , car needs to stop, no way can the standard 328 brakes stop something so powerful, then the clutch, then the flywheel, and it goes on and on and on and on,
after spending all that money u would be like "mmm... should have just gotten the e36 m3" where stock produces 321 bhp and with a lil money can bring it up to about 400bhp..hehe
well anyways hope this helps
maybe try a small turbo kit....
ps, there are some 328 with big turbo kits, but loads of money spent coz always in the workshop..
