I have super 40's on my 02 GT, I can't hear them at all though... I was thinking of going w/a ProChamber... I drove a GT w/an X-Pipe and flows on the street once (got no farther than 3rd gear) and under hard acceleration it made all these scraping/whooshing noises.... does the prochamber do that? And does that only happen at WOT and goes away once your in 5th on the highway? Last but not least, who has the best prices on the PC's right now?