Hey all.

I was thinking. If I bought a completely free flowing exhaust system, like a RB header to free-flow cat (to stay legal), to dual-catback system, that would likely increase gas mileage right? I only say that because it would seem to me that without the stock restrictions (like the pre-cat, and both actual cats), the air would be able to boogie out the pipes. This would make the engine have to work less hard, and would make the car work more efficiently, right?

 

I got about 23mpg average with the true duals, when I went back to stock.. I get about 17 mpg average now.. this is mostly city driving.

 

Correct. If you drive exactly the same as you do now, you'll see improved fuel economy. If, however, you take advantage of the higher flow rates to make your engine produce more power (by flooring it), fuel economy may vary.

-=Russ=-

 

FYI about the high-flo cat, check http://www.rx7.com, they have a Bonez/RB header kit that bolts right up.

Good luck!

 

removed cats from mine replaced with resonator. get about 60-70 miles more to the tank full