Exhaust diameter? 2.5 or 3 inch?

[jackkelly]

Running a hybrid at 1.2 bar boost.

Have a 2 and a 1/4 inch catback to a pro racer backbox.

External wastegate with screamer pipe.

Getting a catback to pro racer made up on Tuesday and I need to know will I go 3 or 2.5 inch?

[jackkelly]

bump

[DevonGT]

2.5 inch.

[RobSR]

Id go for 3" in nearly all instances larger the better for turbos, better spool, lower EGT's etc.

[mikey4410]

would have to agree with bigger the better.

you need as little back pressure as possible.ideally none on a turbo as they dont require it like a n/a does.