Bouncing back to this thread...don't overlook a hydraulic roller if your going in that direction. I run one with hydro roller lifters in the race car and am very pleased with it.
Back to a binding issue ,get a straight line measurement of a bent rod vs. true one and subtract the difference. How much are milled from the heads, gasket thickness ,deck height ? My guess is pushrod length obviously wasn't checked in assembly. Again a real mystery to me that motor ran fine for awhile before breakage Geometry problem.
No raw fuel in the headers ?
What was your run time? Was the initial "tick" immediate upon oil pressure coming up? Was it primed before start up ? I continue to find it hard to believe it was broken in prior to your purchase.
Goes without saying use an adjustable pushrod to obtain proper length this go around. They will vary with machining/cam/rotating assemblies which deviate from stock measurements. Sometimes per cylinder, per I/E. I'm into bigger cube small blocks but has to hold true for " the heavy engines" also.
I would have bet shrapnel made it's way to the bottom of the pan and "machining" to the filter--good for you. Keep us updated on your findings.
(hydro roller/roller lifters, fresh/matched valve train, low maintenance ground pounder with good vacuum and idle characteristics IMO)
No slop, Timing is dead on. I will degree the cam once I go back together with it. After dis-assembly its not as bad as I first thought. The valves were just kissing the pistons and no real damage has occurred. No debris in the oil pan and cylinder walls look great. I will be putting new bearings in the block & on the rods just because. I have checked the pushrod length and it is correct. At first I had thought the pistons were hitting the heads but that is not the case after claying. Same with the P to V there is 0.050" clearance there. I am going to chalk it up to engine not running for 7 plus years and things didnt want to play nice and after it bending the pushrods and me readjusting them it began to destroy the pushrods. After all the pushrods were 1010 mild steel so I guess I am fortunate because it destroyed them and not something else like a valve or piston or cam. Still not 100% yet on the cam. I am old school and I have a Crane blueprint cam I bought years ago. Its a solid flat tappet L78 cam that I may end up using since all I would need is lifters. I am going to go ahead and have the heads reworked and new springs installed and start putting it back together. If it fails again then Ill build another motor or go LSx (since I have the ECU, harness & forged shortblock sitting in the garage. Either way I am pushing forward.
As for the guy that built the engine; I have talked to him and he broke it in and drove it a couple times and when my father got the car he ran it quite a bit and even drove it up the street a couple times. He is not the type that would overlook details but everyone is human. The guy that did the heads has turned out to have a very bad rep in the area and is not longer in business so if there is a problem with heads Ill have the answer as to why and who. Nothing more I can do now but move on and build it back.
Thanks for any and all tips, replies or things to look for. Fortunately this is not my first or last rodeo.