"...I think that the 455 SD's superior torque would allow it to post a higher top speed than a Ram Air IV-powered '70 Trans Am..."
Would an SD455 pull to 6000rpm with the stock 744 spec cam & stock lifters ?
"...You can put 2.41 gears behind a 421 Super Duty but it won't have enough power to pull the gear to redline. That's why the NASCAR SDs typically came with 3.42 gears, because that was the highest (numerically lowest) gear they could pull to the redline..."
I've read that the actual hp of a 421SD was about 450. So, with the forged rods/pistons & solid lifter cam, what was the redline ?