is there a very noticeable difference between true dual and non true dual exhausts? does a tue dual allow more air to come out or does it all depend on pipe diameter/cats? thanks for any input

 

Performance gains from exhausts on an N/A Z are a wash IMO. It really comes down to budget, sound preference and looks.

 

+1 get some hi-flo cats or test pipes if you want to free up some power.

 

^ +1

The only difference with them N/A is sound pretty much.

 

Peak numbers between an Injen and 3" y-pipe with 3" single were the same on 2 identically mod'd Revups I know-same dyno back to back. BUT the TQ curve on the TD was WAY better up top, with much less TQ falling off. On the highway the Injen equipped car would pull out.

My GF recently switched from the Nismo w/tp's to the Fast Intentions 2.5" TD w/tp's and I was surprised at the difference it made past 5000rpm's. Much better pull compared to before. For an HR Id do TD anyday...