I have a stoke bore with a 4.15" crank. From what I remember the cost of the rotating assembly for the 4.15" stroke was the same as the stock 3.75" stroke. I was also told that a stock stroke 426 would have less low end torque than the 440 I was replacing it with. I went with the 472 instead of the 528 because the 528 required a siamesed block and I didn't want to give up any cooling capacity for hot days.