BMW has blessed the E9X M3 with an amazing high revving V8 engine but for such a high strung NA (naturally aspirated) motor, it needs to breathe.
Drop in replacement filters are a nice option but it does not do anything to help the bottlenecking on the intake track. The intake box itself is a great unit. It is sealed, the plastic disperses the heat quickly so it does not become heatsoaked and it takes in air from multiple sources.
The ideal set up would incorporate the stock airbox but create a new intake track. This is what aFe set out to do and they have accomplished this with startling results.
The new aFe stage 2 cold air intake system produces up to 18 max horsepower with 15 ft lbs of torque. It out-flowed the restrictive stock intake by 41%. That’s impressive considering all that was done was opening up the intake track and adding a high flow filter.
This is an integral part of any mod list in order to free up horsepower on the s65.