I like to put Big Blocks ( .21-.32 ) in 1/10 scale cars. One re- accuring problem is not having enough space for the exhuast system. Sometimes we would use .15 size mufflers but alot of times that impaired the motor performance. After searching the net I have found the following Compact Pipes The Schumacher Fusion.28 tuned pipe, Cvec Compact Tuned pipe, RB Concepts TM 523 tuned pipe used on their big block conversion kit for the Revo and Vantage tuned pipe for .18 motors. Do any of you Engine Guru know if any of the pipes listed are any good??