I am going to install the Comp Cams studs, guideplates and Scorpion 1.6 Roller Rockers on my 350. I picked up a pushrod length checker and some low pressure checking springs in order to determine the correct length pushrods. I've been reading all sorts of posts about how to do this, yet I still have a question. Once I get a good pattern on the valve stem tip, and have the length figured out, do I have to add more length for lifter pre-load? If so, how much should be added?

I have a "cylinder pressurization kit" to hold the valves, a valve spring compressor, low tension springs, and a Comp Cams pushrod length checker.

How do my fellow Olds guys do this task? Any tricks I should know that will make this easier? Any other tools I need for this job?

 

I don't think the preload will throw the pattern off. Atleast it didn't for me. Now what I will say is adjust the valve just as you would (preload) and make sure the rocker will not bind up. I had that happen to me. I ordered my pushrods but did not account for preload and. All it took was .030 for my rocker to bind up .