You gotta see this ......
Happens at the same time. Do you think the pushrods that were rammed through those rockers are still straight? I mean, they're aftermarket push rods so I suppose it's possible they held up and the stock rockers didn't, but if I had to guess I'd say they're probably bent.
Like I said earlier, I've seen it. Pistons hit the valves on the bone stock 318 in my GT before I got it. Eyebrow marks on the pistons from the valves, a couple of bent valves, a couple of bent pushrods, and a couple of failed rockers (not quite as spectacular as the OP's). And, that was on a bone stock 318 with the pistons down in the bores, hydraulic lifters, stock skinny little push rods, stock cam, stock valve springs, etc. The stock stamped rocker pockets are not super durable, but the stock springs, cam, pushrods etc didn't cause the damage on mine, some kind of timing chain issue leading to hard parts coming together did.
Here's one of the failed rockers. Like I said, not quite as spectacular, but it would't have taken much more to pop this out
The culprit
And maybe that's not what happened with the OPs engine, but I sure as heck think it's possible, and definitely worth ruling out. There's a few different things that could have been at work in the OP's engine. The fact that it's an intake and an exhaust valve on the same cylinder is worth thinking about. If it were springs, why both valves on only one cylinder? Unless maybe we only have pictures of one cylinder but they all failed?
It's a spring pressure and valve lift thing, it's not unique to eddy heads. The stock rockers aren't that robust. Bigger cam, stiffer springs, more load on the rockers. The ductile adjustable rockers are stronger than the stamped rockers. The adjustment is nice to dial in the preload better, but the strength is more the concern here. If everything is stock the stamped rockers are ok, but start increasing the pressure on them and it's another thing to upgrade.
Happens at the same time. Do you think the pushrods that were rammed through those rockers are still straight? I mean, they're aftermarket push rods so I suppose it's possible they held up and the stock rockers didn't, but if I had to guess I'd say they're probably bent.
Like I said earlier, I've seen it. Pistons hit the valves on the bone stock 318 in my GT before I got it. Eyebrow marks on the pistons from the valves, a couple of bent valves, a couple of bent pushrods, and a couple of failed rockers (not quite as spectacular as the OP's). And, that was on a bone stock 318 with the pistons down in the bores, hydraulic lifters, stock skinny little push rods, stock cam, stock valve springs, etc. The stock stamped rocker pockets are not super durable, but the stock springs, cam, pushrods etc didn't cause the damage on mine, some kind of timing chain issue leading to hard parts coming together did.
Here's one of the failed rockers. Like I said, not quite as spectacular, but it would't have taken much more to pop this out
The culprit
And maybe that's not what happened with the OPs engine, but I sure as heck think it's possible, and definitely worth ruling out. There's a few different things that could have been at work in the OP's engine. The fact that it's an intake and an exhaust valve on the same cylinder is worth thinking about. If it were springs, why both valves on only one cylinder? Unless maybe we only have pictures of one cylinder but they all failed?
It's a spring pressure and valve lift thing, it's not unique to eddy heads. The stock rockers aren't that robust. Bigger cam, stiffer springs, more load on the rockers. The ductile adjustable rockers are stronger than the stamped rockers. The adjustment is nice to dial in the preload better, but the strength is more the concern here. If everything is stock the stamped rockers are ok, but start increasing the pressure on them and it's another thing to upgrade.