1) Backpressure helping low-end torque is a myth.
2) Your sheets look fine. You have gobs of low-end. Maybe you're just feeling it pull to redline harder because of more top-end?

-Philip Maynard '95 Contour [71 STS | Track Whore] '97 Miata [71 ES | Boulevard Pimp] 2006 autocross results