In doing the STS I left my headers, Y-pipe and used the I-pipe from the magnaflow the car was at full spool at 4500rpms, so did some research and found that putting the stock manifolds back on would help keep the heat and not disapate it like the longtubes. So put the manifolds on and got the Bassani Y-pipe and made and I-pipe and the car was crazy it was fully spooled at 3500-3600 rpms. Heres some pictures:
