I am working on a LT1 with a friend of mine and I haven't ever had to change pushrod length before so I dont' know how to know how long to go. He only has about .020" between the bottom of the rocker and the spring retainer. I have never seen a rocker (comp pro magnums) sit at such a great angle as these are I know the pushrod needs to be longer but I don't know by how much. Can I use an approx guess or do I really need to get a pushrod checker. He is using comp high tech pushrods but they are definately the wrong length.

How do we know which one to use

If you guys can help us out I would be so :hail: because if he gets new pushrods I can buy his old ones with hardly any miles for next to nothing. I would really want to have a bettter pushrod

 

One of my friends called me back finally and was able to tell me how to do it.