Checking pushrod length.

[andy669]

You might have to bolt a small steel plate to the head via one of the valve cover bolt holes to give the magnetic base a solid place to sit. Make sure your dial indicator has enough throw to measure the full amount of lift at the retainer. An indicator with a 1" throw is real common. Try to set it up so it is as close to straight with the valve as possible. Set it up on a flat spot on the retainer with the valve fully closed. You will have to put 5 or 6 turns of preload in the indicator so when the valve drops down you will continue reading all the way. Then when you slowly rotate the engine, just count the number of revolutions until you reach max lift.

IMO, with stud mount rockers, this is every bit as important as checking the contact patch. Because of the angle of the pushrod, the angle of the valve, and the angle of the stud, moving the rocker up and down on the stud changes the fulcrum point and can really screw with the lift.

I think its entirely possible to have a decent contact patch and still lose 30 or 40 thou in max lift. And getting that lift back might not make the contact any worse.

Let us know what you find out.

Andy