I have an aftermarket Y-Pipe exhaust and have very minimal hiss with the ART Pipes. With test pipes the hiss was MUCH louder. Now I barely notice the hiss, but with test pipes it was very noticeable.
It is a product of the VQ, so there isn't really a way around it that I know of. Obviously restrictive cats basically eliminate it because they disrupt the air stream so much. I don't have any personal experience with true dual exhausts but I have a feeling that they could possibly minimize it some, but who knows. I will say that the hiss definitely comes from the Y-Pipe. I have gotten under my car and listened to someone rev it, so I know this is the case. But, if you had a true dual, it could still come from the same area.. so who knows if it's a y-pipe thing or it's just a VQ thing.
__________________
2007 350Z HR :: 3.7 Final Drive : Injen Long-Tube Intakes : TurboXS Cat-Back : Eibach Sportline : Enkei RPF1 18x9.5/10.5 +15
|