Quote:
Originally Posted by atmosphericM
Err'one here pretty much agrees that you can't go wrong with the OEM box (charcoal filter removed), Eurobox, or aFe sealed unit (stage 2 si). If you stay OEM, grab a silicone intake elbow from Rev Motoring, get a filter of your choice, and call it a day.
|
Great summary and wrap-up to a frequently asked question.
The intake above, plus an auxiliary snorkel CAI similar to the E9X and E46 M3 designs, measured over 16 whp gain on the dyno.
A closed intake system that sources O2 from outside the hot engine bay (like the PI and AFE boxes) make more power by decreasing IATs. The aux CAI makes more power by increasing O2 and further contributing to lower IATs, and the ECU attempts to maintain target AFR.
This isn't debatable:
http://iopscience.iop.org/article/10...3/1/012039/pdf
__________________
2011 6MT RWD ClubSport Wagon | 3,185lbs | 1 of 149 ZSPs delivered in North America
Outside: BMW M-Aero, Euro region lighting, Seibon | Inside: M3 cockpit, Recaro SPG, Prototipo, AutoSolutions SSK, UCP | Stop: M3 ST-40R, PFC | Grip: Solid-mounted subframes, rear coilover conversion, M3 Nitron R3, Hyperco, SPL, AKG, ARC8 | Go: StageFP, CF snorkel, 3IM, MILVs, SuperSprint headers, Dundon Motorsports Inconel exhaust, VoltPhreaks | Cool: CSF | PCA #2018100384 | BMW CCA #505794