FEULING PARTS 1010-2832 5402 3" Velocity Stack with Backing Plate Kit - ChromeFeatures Impressive horsepower and torque gains on engines running modified and ported cylinder heads and intakes with larger throttle bodies Great performance part for racing and for those that want to head to the track on the weekend Includes backing plate and all necessary hardware for standard head breathers 3 tall billet aluminum velocity stack fits M8 throttle body 3 hole bolt pattern 4 diameter opening with an internal taper down to 64 mm ID