Outer Limits 4x4 Board

Hey all,
Just wondering if anyone has any oppinions on running a 3" exhaust on a 4.5 petrol gu motor with extractors and aftermarket computer etc?

I would probably one day like to turbo the motor so I was thinking I could use the 3" zorst for both rather than spending heaps twice.

I don't want to hurt power production on the naturally aspirated engine in the short term though.

Have been told 2.5 would be best but is there a good reason why a 3" wouldn't be any good ie would it end up robbing power?

It is a big motor so I am unsure.

Cheers
Brian

hey,
the only thing I can think of that may pose a problem would be the lack of back pressure , could this be an issue with a 3inch system??
Once you have fitted the turbo, the 3inch will be ideal.

back pressure is a fallacy. as long as the extractors are scavenging the difference of 1/2 an inch on the exhaust will be minimal. if ur planning on going turbo buy the 3 inch.