just got a magna flow turbo back 4" straight pipe installed. on the first start up i heard alot of hissing, looked in the end of the pipe and saw some metal build up where the end of the pipe was cut with a chop saw before the tip was installed. i asked them to trim out the metal with a die grinder which they did. it cut down on the hiss but it is still there. is the hiss normal turbo noise or do i have more metal build up on another pipe section deeper in the exhaust system that needs trimming? i did notice that on a cold start, for the first second or two, the exhaust sounds deep with no hiss or whistle, then the hiss kicks in and the whistle starts to build. i think it might just be the turbo but would feel beter about it if someone would confirm it. i really dont want to take all the clamps loose to check each section end for hiss causing metal build up from the chop saw if its just nornal 04 turbo noise. by the way, the turbo whistle is awsome.