Eventuri BMW E9X M3 (S65) Black Carbon Inlet Plenum - GlossIntroducing the E9X M3 Carbon Fiber Plenum from Eventuri. Made from 100% high grade prepreg carbon including the internal trumpets, this plenum replaces the stock plastic version and unleashes the roar of the naturally aspirated BMW V8 engine. Since the trumpet lengths are tuned by BMW to the internal volume, changing this could result in a loss of performance so we kept the same volume to not upset the way the car drives in terms of power delivery.