I dont think this problem is too common, but on my 1.4 RT clio mk1, ive got a Powerflow cat back system, it sounds ok ticking over but when you drive it, its just too loud and it sort of humms irritatingly in your ears. Dont get me wrong i like a loud exhaust but this is just annoying now 6 mths down the line. Ive got K&N but its not fitted as yet, is it worth putting that on?? Or how can i reduce the sound, the boots full of underlay (and that made no difference)Is it the case for a new back box even?
cheers