Altered-stroke engines are not for the novice engine builder. True, a "kit" is more likely to accomodate the guys who can't or won't go to the trouble to understand what's involved in making such a basic change from what the factory engineers chose to install.
I got introduced to stroker engines back in the early 1950's, with the flathead Fords Dad built for the local 1/4 mile dirt tracks. There were no such things as engine kits back then, so the only people who built stroker engines were the ones who could engineer them to work properly. The standard Ford V-8 stroke was 3 3/4", and the 49-53 Mercury had a 4" stroke crank. The Mercury crank could be offset-ground to a 4 1/8" stroke by using the smaller-dimension connecting rods and bearings for the 85 HP 1932-38 model engines. Beyond that point, strokers were either welded up to increase the radius, or whittled out of a solid billet of steel. I've seen a few drag-racing flatheads with a full 1" stroke increase, out to 4 3/4". Those cranks won't survive on a dirt track, they twist the center main bearing in two!
Jerry
