It appears that after reinstalling my factory exhaust my gas mileage has increased. Could this be due to the factory ecu being programed to operate most efficently with the stock level of backpressure? I always thought that a more freeflowing exhaust would give better gas mileage.

 

You probably wanted to hear the aftermarket exhaust more. To do so, you must smash your foot on the accelerator, thus producing less gas milage!

-Cody

 

Of course...when you add power with mods, you use more fuel...power comes from burning more fuel