what happened with the pushrod length problem?
Its a long story but the pushrods were too short and the threads on the rocker adjuster nuts were not fully engaged. Also the preload (hydraulic lifters) was not properly set.
We were making T&T runs and all of a sudden the car started going faster and faster. In 3 runs it dropped around 0.8 seconds! On the final run it lost the water pump belt and overheated.
When it overheated 2 pushrods fell out. That's when I found out the valve train was a mess. I found several cups in the lifters with cracks.
At that time the lifters looked suspicious but not real bad. 26 runs later the lifters are shot.
I have put upteen cams in my cars over the last 35 years. Never had on fail due to break in until now. There is definitely something to be said for today's oil and metallurgy. I'm going with a hydraulic roller..........
Sorry to hear, What a PITA.
"Knock on wood" add me to the camp that has never lost a cam. I have never started a motor with the lash or pre load wrong either.
The cam now in my 340 is in it's third engine with original hydraulic lifters and I have always ran the same original crane gold adjustable rockers. On iron heads and on edlebrock aluminum heads. So I always set the pre load for each lifter on the engine stand. And I beat that car/motor hard now for 26K miles since the last freshen up including like 5 trips to Bonneville where I beat the car for miles at a time over 100 mPH easy.
IMO you can't blame the cam or lifters if the pre load was wrong, even if it's only for a short while. If that happens all bets are off, imo. If all that was perfect and you were keeping an eye on the lash pre load then I was start doubting other stuff.
I would take the motor out and all the way apart and clean it out. Like you said the cam is junk now too. I surely don't blame you for going hydraulic roller, but maybe a solid roller would make more sense? More RPMs for sure.
Make it so you can adjust the valves, That way you keep an eye on the cam lobes through valve lash. Got to pull the valve covers often, it's just good therapy. Do it often and race with confidence. Maybe she can learn to adjust the valves? I taught 3 guys to do it on my dragsters. Although I realize a dragster is 10X easier to work on, no fenders.
