kurt454 wrote:You using two different gear ratios in your two engines. Equalize the gearing between the two engines and the 455 dominates.
Towing is not a contest of acceleration over a broad rpm range. It is brute force(aka Torque) being applied at a fixed speed.
The 455 in your OP has a 511 ft-lbs of peak torque. Your 400 is showing a peak of 465. With EQUALIZED GEARING the 455 can pull a heavier load. Big engines are not just for durability.
Kurt, I'm not trying to be disrespectful so please don't take it that way, but you are wrong. The 400 will be able to tow a greater load at EVERY MPH because it has more HP which can ultimately be reconfigured into a greater torque at the wheels than the 455 at every MPH due to the torque multiplication of using a higher numerical gear. This is the whole point of this exercise.
Why would I equalize the gearing for a 3.75" stroke compared to a 4.21" stroke?