I have had the heads on my 390 GT rebuilt and i think it may be the second time, Anyways they had to be rebuilt because they did not have harden seats and the valves pulled up and I had no compression in 3 cylinders. The machine shop also milled the heads .015. The push rods I took out were 9.62. I know I need to replace with shorter push rods.
I am reading the ford manual and it states to measure the following:
Valve stem to valve rocker arm clearance should be within specifications with the hydraulic lifter completely collapsed. Section 8-1 page 8-9. I am looking at the clearance specs, Page 8-135, and that seems to be quite a gap. 1/10 of an inch?? Am I reading this right or is this a misprint.
There is another method to measure pushrod length and I have a pushrod checker, but what I do not know is what the lifter preload should be.I saw one site online mention .05. Is this correct? BTW, I am at TDC and reading Cylinder 1. The lifters have bee replaced.
Finally, I have measured using the method above and I am coming up with a pushrod length of roughly 9.4375. This is quite a difference from 9.62. It seem to great, what am i doing wrong.
Thanks for any input, Larry