i read in some magazine that a good rule of thumb is the have about 12~14in of piping after the header flange before you weld in a cat/resonator/muffler, so that it doesn't affect the flow pattern of the exhaust waves right out from the header. What do you guys think? i'm thinking of making a semi-dump pipe that looks like the one offered by comptech. (i don't think they offer it anymore...i can't find it in their website.)

 

oh and also, is there a recommended distance between resonators/mufflers?

 

any inputs? ??