Broken rocker arms two weekends in a row

inertia said
Is it possible you're spanking a valve, I used to poke a pushrod thru when I missed a shift and spanked a valve.
If you got a bore scope, see if you can see a witness mark on the piston.
Maybe interference with the retainer and top of the valve guide.
Weak valve spring ?
Same cyl ?
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Did that, no evidence of any witness marks on the pistons. These valve springs have around 120 mostly 1/8th mile runs on them since installed new. Can't see any sign of retainer to guide interference. First rocker that broke was #4 exhaust, second broken one was #5 exhaust.