Hello all,
I have a 1989 300ZX turbo and i want to do a custom exhaust on it. Im going to leave stock headers however after that, I am doing a High Flow Cat, then straight piped back to a muffler. Now for the muffler, What do you guys think would sound better? 3" Pipes 3" exhaust outlet? 3" pipes 3.5" outlet? or bigger?

Any help would be much appreciated!

 

3 inch all the way out.

 

So that would sounds the best then? I was this to be a loud deep tone

 

I will tell you my set up on my 86 turbo It was completely stock and would roast the left side inner tire . I removed the muffler and went with a straight thru cherry bomb type and a larger Cat , it fixed the problem . it has noticeably more power 2-4k mostly . get ready for a drop in mPG though 3-5 IMO
the frt pipe is 3" already with the rear 2 1/2 or 3/8, you won't gain much for the $$
I did the flared tip which at 60mph + gives a bit lower pressure ( the aircraft cowl effect)
but quicker flow can cause more heat in the system and damage parts quicker in the engine side especially if it cannot richen up enough

on a carburated engine, freeing up the exhaust requires a rejetting or richer mixture