crank stroke

[lookingaround]

i know where a crank is that is suppose to be for a 421. how can i tell if its the right stroke? i think 3.875. its for a 400 small block chevy

[zipper06]

Yep,
414" with std. bore of 4.125, 421 wth .030 over =4.155 bore

Zip.

[performanceengin]

most aftermarket cranks are marked with stroke on front throw.