Im planning my head cam build up and something I came across was different pushrods. I know I want to get chromoley but what length? The heads are getting milled to bring my compression up to 11.5:1 with an impala gasket. Is there anyway to figure out what length you need? Will it need to be shorter or longer?

 

A shorter pushrod is not what you need. There are too many variables such as cam base circle, block deck, gasket thickness, head milling and valves length.
You'll not know the correct length unless you measure it, by a pushrod checker.
I've a small base circle cam, 0.020" decked block and a thiner gasket. Ysing the pushrod checker I found the perfect length was the stock 7.200".

 

Just to second sssalah's opinion (he seems to know his stuff): it needs to be checked when significant changes (such as milling the heads) are being made to the combo.

Rich Krause