going with lt4 hotcam, edelbrock vortec etec 170 heads, what length pushrods do i need

 

Unfortunately there could be a fair amount of variance that wouldn't allow a cut and dry answer. The stock length should work. The only way to be sure is to buy an adjustable length pushrod tool and check. With my Trick Flow heads the stock lengths worked but with my AFR heads I had to switch to a different length.

 

If it's not all stock, then you've got to measure. Take a look at a short thread I had started when I was measuring for mine. There's good input in that thread on how to measure accurately.
https://www.thirdgen.org/forums/tech...od-length.html

 

definitely measure. Adjustable pushrod and checker springs are cheap. I Borrowed a spring compressor from a buddy but I bet you could rent one from Advance or one of the parts places.

 

Checker springs are good. another idea for them is 1/8 scale RC car shock springs if you know someone that runs RC cars can just borrow them to check it...