ok so does anyone know what crank rods and pistons are used to stroke a 302 to a 347. for example a 400 crank turns a 350 into a 383. and how much more power will a get from a set of gt 40 heads i have 1970 351w heads now.

 

Aftermarket crank 3.4 stroke 5.4 rods or they have a shorter rod that is 5.390 or some thing like that and custom pistons depending on rod selection and .030 overbore. they use to cut down 351C cranks to run them but with the aftermarket on the seen why bother. I don't think the gt40 heads are gone to give you that much HP over the 70 351 heads.

 

why bother with gt-40 heads