2dr LS 4WD - WHAT'S THE MOST FUEL EFFICIENT EXHAUST?

[doc5339]

I was about to buy a 2004 Colorado and get rid of the Tahoe, but I can't seem to bring myself to do it. That said, I'm trying to make her more efficient, even if it's only slightly.

My only mod is a K&N air filter, but I'm thinking of a twin Turbo exhaust, not for power but efficiency. Any input is greatly appreciated.

[1cbtengr78]

Did you purchase the K&N Filter that replaces the stock filter, or the FIPK kit? I bought the stock replacement filter and it almost seems as if my gas mileage became worse. How is yours working out?

[doc5339]

I just got the replacement filter, but I didn't notice any major difference in MPG. I guess the more air you let in, the more fuel the injectors add, according to the sensors/fuel map?

I'm looking at getting twin Turbo exhausts in hopes of getting at least slightly better mileage. I do know that most all stock exhausts setups are usually very restrictive.