Interesting. Several years ago, I was trying to build a 454 using a production 400 block. I had a 4-1/8" stroke crank lined up, but it turned out to have cracks. Couldn't find another for a reasonable price. Ended up building a 434 using a 4 inch stroke. The block had to be clearanced, and a special cam had to be ground. Makes one hell of an engine. /forums/images/graemlins/waytogo.gif Used it in a mud drag truck.