Engine in distress?

[grant6395]

I have a customer that I built a 427 sbc for a few years back. It has a g- force face tooth 101a trans in it. Twice now , he has managed to get it into first gear while going for 3rd .( clutchless) . Both times it flung the belts off etc. He checked the lash etc and all is ok there. No bent pushrods .. blah blah. Anyhow, by my calculations, with the clutch locked up, the engine would have gone close to 9800-10k ish. ( gear ratio/ rear gear/ tire height/ in second gear at shift point is approximately 64 mph. This being 7300 shift. If you calculate first gear ratio into the equation, at the same , or close mph, it come close to 10k. Give or take with clutch slippage etc. The engine has eagle rods/ 2000 bolts. Eagle crank. A mile of ptv clearance thankfully. Should this thing come apart? And what should I be looking for? It ran fine so a visual inspection won’t say much in my opinion.mag the rods etc?. The lifters and springs have been changed since. It’s a 650 hp solid roller cam stove Thanks guys. Sorry for the long winded post.

[MadBill]

I wouldn't worry about the rotating assembly for such a brief over-rev, but I'd say a leakdown test is critical, and any exhaust valve leakage would be cause to pull the heads. Better would be addition examination with a borescope to look for valve contact spots in the piston eyebrows. Best would be to play it safe and remove the heads for better visuals. The problem is often that the valves get tweaked, but don't fail until a bit of post-incident run time flexs them back mostly straight.

BTW, a roller cam system usually has more over-rev leeway since being quite insensitive to spring load, they tend to be specced on the high side.

[grant6395]

Thx Madbill. Good advice. I peromed a leakdown and all seems well. I guess he will carry on with it.

[cjperformance]

I have to say that I would be pulling the pan and checking rod bolt stretch by measuring as they are then remeasuring once released. Or simply replacing rod bolts. Cheap compared to spitting a bolt after a few more runs.

[SupStk]

Other than what Mad Bill suggested I would magnaflux the rods. Eagle H beam rods in endurance applications (boat racing) tend to develop cracks on the surface around the threaded area. Haven't seen one break yet but cracks never get smaller with use.

PS. Fix the shifter!