My cousin & I did that back in the day when he 1st put his dads old 340 4 gear duster back on the road after a decade of sitting, use a smokey low cr 318 short block with his dads ported 340 TA heads, 750 and fairly aggressive cam he had laying around it ran pretty strong imagine the 4 gear helped and going from 3.23 to 3.91 really woke it up, but apparently should've been a turd. Even ran the short block in his late model with the late models top end and kept up with cheating Chevy's :)
