Sounds like fun!

Any updates?

I'm headed to mill my 5.3 heads soon... Was planning on only doing .030 - .040.

 

We, and most on here will recommend checking pushrod length instead of guessing what length you need because variances in all parts of the valvetrain could be off/different than someone elses setup (even if they are using the exact same parts).


Basically when it comes down to what can cause these differences(I will name what I can think of off the top of my head, if anyone can think of something I have missed please feel free to chime in):

The deck surface on GM blocks can differ from block to block, which can cause a different pushrod length.

The cylinder head deck can vary from head to head (be it GM, aftermarket, reman, etc...), thus changing pushrod length.

Valvestem height due to either a valvejob, or different stem length can cause the need for a different pushrod.

Different camshafts with different base circles can require different pushrod lengths.

Using different lifters that require different preloads can change pushrod length.