I searched for this but did not see any thing close, so here goes.

If not in my signature, 1997 Z28 LT-1 327 block number, Engine going in is a 1995 LT-1,327 block number. 1.6 Summit roller rockers

Questions;
With the cam that I installed, (see cam card photo) and the stock push rod installed I got the following bad pattern, (see photo).
With a push rod length checker I got a good pattern, (see photo).
Comparing them on a scale, (see photo) it looks like I need some shorter push rods.
I used a comp cams kit, LT1 280XFI HR-13 CAM and KIT. The springs are longer and I am using Summit 1.6R roller rockers
Does it seem right that I will need shorter PRs?

All photos are 0 lash + 1/2 turn.

Thanks for any feed back on this.

Stock Push Rod Pattern

Push Rod Length Checker Pattern

Top PR Stock Length. Bottom PR length Checker

 

Looks like I might have to re-measure the stock push rod length...........

 

OP

It is common with motors that have been rebuild (block decked) and heads refreshed and sometimes using a thinner head gasket than stock a shorter PR is needed to get the geometry correct

Your sweep pattern shows you need a shorter PR. I have the 466 cam and wound up needing a 7.100" PR. Set up your PR check tool at 7.150 and 7.100 and see which one gives you the most centered AND narrowest witness mark pattern and order those PR. I got the thicker, hardened, .080 wall Trick Flo PR as I use guide plates (ISKY)

IMHO if you used Comp 918 springs...keep an eye on them (read check each one every 5k mi) as my XFI grind killed (read broke) the 918's (in under 20k mi) which were installed at 1/800". I went with the Lunati LT1 spring kit I bought from Lloyd.