How old are your rocker arms- what brand are they?
I broke some studs last year and traced the problem to bad rocker arms. Hold the bearing shaft and move the rocker in your hand and see if it is smooth. I replaced the rockers and installed ARP studs.

I am sure that stud girdles will help if you have room underneath your valve covers. Lay a straight edge across the studs and see if any are out of alignment with each other. This would indicate that they are probably out of alignment with the valve stems.
Sincerely
Dennis Moore

Tinkerboater, new rockers, and they are smooth.

Thanks Dennis I'll check the alignment.

Some of my rules for valve train set ups.

Long life .500 and under lift for small blocks
.550 and under lift for big blocks

.600 and over stud girdles or shaft mounted rockers.

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