So i put used invidia straight test pipes on my 07 G35. I got Borla Performance Muffler and 3 in mid pipe. Y-pipe is stock. Its sounds great below 3k rpm but get pretty raspy above 3k. Should I get new resonated test pipes or replace stock y-pipe with resonated one. Or should I resonate both. I dunno..opinions?!

 

Your best bet is to get the Motordyne XYZ pipe with resonator. It also has a 3" outlet.

 

Are there any knock-offs...I really dont feel like paying almost $500 for a y-pipe