[blykins]

I personally don't know why anyone would choose a smaller displacement when all the parts cost the same.

I have sold/used (2) of the 4.125" stroke crankshafts. I have sold/used countless numbers of 4.250" stroke crankshafts.

You get about 1.1-1.2 hp/ci, so that extra 14 cubes will do nothing but add horsepower/torque for the same money.

The 4.125" and 4.250" cranks are drop-in on an FE. The 4.375" is also drop-in, in 99% of situations.

The stroke/rev-ability is a farce. The stroke may be shorter but you're adding a taller and heavier piston on the other end. There is a tremendous amount of variables that go into how quickly an engine will accelerate. Just looking at the stroke is one of the goofiest things you can do.