WTF is a 283!!! A chevy crank wont fir in a 360, and anyways, a 340,318,273 all have the same stroke, the 360 has a longer stroke. 340 has a .040 bigger bore than the 360. the 360 currently in Lori's Duster pulled all the way to 6700. I stopped because of vavle float. Actually a 383 stroke is 3.38 and a 340 stroke is 3.31 So I actually would build a hi revving 383. Any other questions?