Those of you who have installed exhaust and HFCs (Fast intentions in particular), How does it affect your fuel economy? Anyone seen a noticeable difference?

 

I have both the FI Exhaust and the FI HFC's. Before both of my mods: I drove my car pretty hard most of the time and I was getting around 15 miles per gallon. After both mods still driving the same and still getting the same gas mileage. So its the same for me.

 

same. depends on how you drive.

 

These mods should slightly increase your mileage but it often doesn't because people tend to drive more aggresively than before. Any free flowing cats and exhausts should increase engine efficiency.

 

damn 15 mpg! u must drive it really hard! but i guess after you get those mods its probably harder to drive normally....

anyway good to know theres no negative effect on fuel economy..thanks guys