Guys,

 

Ive decided on the exhaust im going to get, but im unsure of the following

 

Should i go for 2.5 inch diameter pipes or the 3 inch diameter? (talking about the actual pipe sections as opposed to the tail pipes)

 

Obviously im going to have to go for the 3 inch de cats with suitable downpipes, but is there such a thing as having too little back pressure in the system?

 

This is the rough engine spec i intend to be running to match the exhaust:

 

Z1 side mounts

Nismo 555's (for a '95 car which i think are running 610cc's)

JD ecu

K&N intake

and probably Profec boost controller at around 15-16 psi mark

aquamist water injection

And prob an uprated fuel pressure regulator

 

Now im taking a stab in the dark at these should make the engine run over 380fwhp and 350 lbs/ft (guessing from how steve 300zx '96 running 406fwhp)

 

Now with the rough guess in figures, would i be getting anywhere near the maximum flow capacity of a 2.5 inch system, or would a 3 inch system be worth investing in?

 

Over to you...

 

Nick

2.5" will not cause ANY problems... A single 3" system is good for at least 900bhp so.......

Cheers andy,

 

In an ideal world id probably like to run at a 450rwhp/450lbsft, so tubs etc would come later, infact, ALOT later but if a 2.5 system can handle that then there seems like no point going for the 3 inch.

 

Cheers again