Originally Posted by aschon
thinair - I'm just saying.. BMW's respond really shitty to bolt-on's.. it's almost a waste of money to mod them...
So what you're saying is that BMW properly designed the parts that came stock, and that aftermarket companies don't have much room to improve on.
I don't think you understand how much faster a 328 and an M3 gets with a shorter diff, cams, manifold and software.
Originally Posted by BennyL
so does anyone wanna explain to me what each of these is:
3.15 LSD, M50 Manifold , Fan Delete Mod Kit, M3 Catback, Stock Airbox Debaffle + K&N
3.15LSD - a differential with a 3.15:1 gear ratio, and has limited slip (Limited Slip Differential) so power is forced to both wheels. Stock on a 328 is a 2.91:1 gear ratio. This mod only really applies to 325 and 328's.
M50 manifold - the intake manifold on the M52's is restrictive, so many people swap in the manifold from the M50 engine (325, 525, 95 M3) into their 328's and 96-99 M3 engines.
Fan Delete Mod (FDM) - this modification removes the radiator fan that is bolted to the water pump, relying primarily on the electric auxilaury fan and a cooling system that opens the coolant to the rad earlier. The engine fan requires about 3-5hp to be turned.
M3 catback - a stock muffler from an M3. It's called catback because it's the entire section that bolts onto the catalytic converter and exits at the rear of the car.
Stock airbox debaffle + K&N - there is a noise baffle inside that stock airbox that can be removed for improved flow, the side effect is more induction noise, which is good or bad, usually depending on your age
. K&N is a company that makes reuseable cotton air filters whcih claim better flow then stock paper filters.