Horsepower is torque multiplied be engine horsepower divided by a constant (5252). This means that really the only relevant factor in this scenario is engine horsepower or better yet how the engine power curve is best utilized.

Drag races are won by whoever utilizes the power curve the best with their shifting. Assuming we're talking about identical drivetrains, it really boils down to whoever is maximizing the area under the power curve. This means if you shift exactly at peak power you're actually dropping way off the power curve where the engine makes less power. Ideally you want to shift somewhere after the rpm where peak power occurs so after the rpm drops down from the hear change that you're as close as you can be to making peak power again. A lot of the time this means shifting at redline because of where peak power is on the rpm vs hp curve.