I just built this motor.
I used 72cc swirl port TBI heads. They make good low end torque and do nothing over 4500rpm
Mtc1 cam :high lift short duration good low end torque
Flat top pistons 9.25:1 compression
Cast iron manifolds, 2.5" dual exhaust with an H pipe
Hei and a Q-jet
That is a low end torque combo. ...at least I hope so. It's still setting on the engine stand.