Bought new heads for my stock 454s. Head mfgr says I need to check for proper rod length. So, I bought some appropriately sized "push rod length checker" gizmos. One size for intake and another for exhaust.

Question is, I don't know how to use these things. Do I go by feel as when setting up the valve train? Or, should I be measuring lifts?

Thanks for any help.

If you have never done this check before, the best place for information on how to do it is on CompCams website.

http://www.compcams.com/Technical/Products/Pushrods/

Thanks for that link Checkmate. Read through it, goog thing I did. However, CompCams was referring to a roller set up, mine is flat tappet hydraulic. I'll have to do some more investigating.

It basicly works the same way. You want to end up with a small contact pattern centered on the valve tip.

So, basically as perpendicular as possible (rocker to valve)?

As was said, it doesn't matter what type of rocker arm you are using. The contact pattern should be the same. Just follow the instructions on that link.