Quiet Insert

Easy, bolt-in sound reduction for 3″ HP-Plus® mufflers; Takes off 4dB at idle and improves low-end torque – minimal loss of top-end horsepower; The machined discs with tapered bosses fit into each end of the patented resonator near the exit end of the mufflers and are retained by the supplied bolts and nuts; This kit is designed to use with three-ball style resonators that are 6-1/2″ long; Will also fit most other mufflers (four-ball style resonators) if 1/4″-20 x 11.00″ threaded rods are substituted for the supplied bolts; Installation requires removal of the mufflers; Kit includes machined discs and (2) 7-1/2″ 1/4″-20 bolts and two prevailing torque nuts; Made in the U.S.A.