I'm currently running z1 HFCs with a megan racing y pipe and stock y back. At the moment it's rasp city. I've read that maybe the megan racing y pipe is creating a lot of rasp, but I've seen a video of a guy with my setup but oem y pipe I believe and still had rasp. Will getting the more free flowing y back AND oem y pipe fix my rasp issue? Thanks,

 

I doubt it will fix it but going back to OEM y Pipe will make it alot less noticeable. All g's have rasp but depending on the set up is how noticeable it will be

 

This reduced my rasp. Original owner put on berk tp oem y pipe and top speed y back. I replaced y pipe with motordyne y pipe and resonated xyz Pipe. Much much better.

 

Motordyne resonated y pipe is the way to go with the Top Speed exhaust. I don't feel the oem y pipe would help since it doesnt have resonators, unless the smaller diameter is helping somehow.