Hi,

I've tried searching but had no luck finding any data to compare using a 50mm or 60mm exhaust on a turbocharged GD3.

From what I understand, a 50mm will give me a faster spool up but lack a bit of top end whereas the 60mm will be the reverse?

I currently have a full 50mm 5Zigen exhaust but I am ordering the HKS turbo kit and a heap of other goodies, so I want to know do you recommend getting a new 60mm cat back or just stick with the 50mm?

I'm aiming for ~130kw atw on 8psi so if 50mm is going to cost me a fair whack of top end I'll get a 60mm. Just looking for people with experience to help me out

 

i have a 50mm (2") full exhaust (turbo back), no cat.

im sure there are more gains to be made if i upgraded to 2.5 or 3", but i dont feel the gains vs noise are worth it.

you can barely hear my car running at idle. no drone on the highway. sounds GREAT when i drive hard. my g/f hates modded cars, and she is yet to complain. that says alot.

im making an estimated 170whp on a dynapack with this exhaust.

 

Sweet thanks, I don't want to go through the pain of having a loud exhaust (last one on my Skyline was well over 100dB and used to rattle windows in neighbour's houses). I've got to have a cat (or $$$$ dollar fines) so I'll probably need a slightly higher flow version than the stock one.

 

check out the vibrant high flow cats. you could weld one into a test pipe.

 

I have a 2.5 from the downpipe back...sounds great...no regrets...BUT I have a very small resonator, a "turbo" muffler from autozone, and a fart can out back....

 

the turbo kit Im getting runs a 63mm exhaust.