So currently I'm running Berk HFCs, 370z HR Y pipe, coupe middy, and HKS rear muffler... here's some sound clips since i know someone is gonna ask.. Of course it sounds better in person..





But heres my problem... at first i thought the resonator in the middy was done.. i got a flapping/leak noise after u rev the engine... so after months of dealing with it, i couldnt take it anymore.. i swapped my stock 06 sedan middy back in and.. the noise was still there... the problem is the HFCs are blowing air so hard into the Y pipe that it actually resonates and makes a leaking noise... so to solve this problem i decided to call up my exhaust shop and have them make me straight pipes from the HFCs to the muffler... i know its gonna be significantly louder, but can anyone shed some light as to how much performance is going to change, will it be noticeable? Looking forward to some suggestions and advice if anyone had or knows someone with custom piping..