I had an ultraflow put in and have noticed about
a 2MPG increase.
Before, I was getting low 16s MPG driving VERY conservatively.
Now, getting low 18s driving moderately aggressive. That exhaust
sound makes me want to slam the gas pedal down every time.
Still trying to figure out how some people are getting up to 20MPG.
My Butt-O-Meter
tells me that I lost a very slight bit of low end, off the
line torque. But have gained better response in mid to upper end
power.
a 2MPG increase.
Before, I was getting low 16s MPG driving VERY conservatively.
Now, getting low 18s driving moderately aggressive. That exhaust
sound makes me want to slam the gas pedal down every time.
Still trying to figure out how some people are getting up to 20MPG.
My Butt-O-Meter

line torque. But have gained better response in mid to upper end
power.