[HWYSTR455]

Too many misconceptions regarding over-revving, it's basically folk lore.

First, 'back in the day', when you heard people 'over-revved an blew up an engine', was due to cast cranks, rods, and pistons. The engine in question is not a stock engine.

A lifter pumping up doesn't destroy an engine, period. If that were the case, what about solid lifters?

Generally, over-revving causes valve float. There are other factors, such as weak spring etc, but valve float, worst that can happen is a piston contacts a valve. If that happens, it bends the valve stem and/or the pushrod. That's it. It would take a lot more to break off the lifter bores.

Think about it, the valve goes into the chamber at an angle, the piston would hit the edge of the valve, the valve would take the hit, not the block. A valve bends before the lifter bore breaks.

If it's a cheap 2-piece valve, the valve head can come off. If that happens, it falls into the cyl and beats the head/piston causing damage, maybe block damage, but not the lifter bores.

If a valve bent, it wouldn't close all the way, and you would be able to tell by the spring not being at the same height as the rest.

MAYBE the block already had a weakness, but that would usually get picked up in a sonic or magnaflux check.

MAYBE the piston to valve clearance was close, and the valve/lifter floated, which could have struck the piston. But then again, it would bend the valve, not break the lifter bore.

The ball broke off the pushrod, that takes considerable force. It's more likely there was critical bind in the valve train, which caused that, and if the valve isn't bent, the bind happened before the tip of the rocker on the spring side.

You go to your builder and tell him it was your fault because you over-revved the engine, he's going to leave you believe that, and you will be responsible for repair. (And him off the hook of responsibility)

My guess: Incorrect rocker geometry caused bind, due to using the incorrect rocker.

As another posted suggested, a pic of the rocker underside will show a witness mark.

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