The larger exhaust has moved the peak torque curve from 3500 to 4500 before to 3700 to 5300. Horsepower was lower slightly until 4000 rpm where it gradually grew to 40 more at 6300.

I ran 12.19 @ 111 with first set up. I think moving the torque curve up an increasing hp should throw me in the 11's.

The dyno operator suggested going back to
2 1/2 exhaust. He thought it would increase torque to about 450 and drop the curve back. Since I never get below 4000 rpm when running I'm not sure I agree.

I think I need to run as is and see where we ended up.