I just bought an '01 with stock muffler. While driving back to Vegas from San Jose, I got 360 miles of range. When I got home, I put the Flowmaster from my '99 onto the '01... It KILLED the milage! It went down to 280 miles... so, I switched it back to stock.

Pros: GREAT sound... but not so loud that it attracts the Po-Po. Also light weight...

Cons: Very low back pressure... VX needs at least SOME! Killed the MPG and power. Power band had a flat spot during spirited acceleration. Switched to Stock muffler... power and mpg came back.

Question... is there an insert that can be installed that will increase backpressure, and not quiet it down too much?
I've seen the thread about the insert for quieting a low backpressure muffler, but not the other way around.
???