Help with a rocker question. As you can see in the pic this one is severely overheated. The pivot wore out and the rocker came off the valve. It's a new engine, small block Chevy 383. I've built my share of engines, but this is my first experience using a roller cam (hydraulic). I broke the engine in with a single set of single valve springs that were on the heads, since they only had about 20 hours on them. I know rollers really don't require a break in like a traditional flat tappet but since springs are easy to change on a small block I wasn't taking any chances. Ran it for an hour or so in the boat (no driveshaft to the jet) and then took it for a spin in the local lake to work out any bugs. Didn't hammer on it too much since I didn't want to float any valve and the lake is pretty small anyway, but I got the RPM's up a few times. So I changed the springs to a dual set, they had more pressure than the recommended ones since the ones called for wouldn't fit the World Heads without removal and machining. But not much more, only about 20 #'s, ended up being 155 closed and about 340 open, I don't have my build notes with me but those are the numbers I remember. And I've seen different companies call for similar pressures for less cam. It's not a big cam only .520 lift. Those rockers were from the old engine, worked fine with the single springs during the break in and the first outing, and when I changed the springs they still looked normal. My question is "Did I just commit a rookie mistake?" When you start dealing with those kind of pressure does that become full roller rocker territory? Is that ball assembly just not up to the task? A few of the others look overheated also. I don't think it's a lubrication problem, I have 30 psi idling and 60 cruising, and the ball ends of the pushrod and the seat of the rocker don't show any signs of galling and I can't catch a fingernail on any part of the ball if I spin the pushrod but I will look for other signs if you can point me in the right direction. That damage took about 1/2 hour of being on the river with lots of full throttle blasts although it only turns the impeller 5K. So if I am going to need to step up to a set of rollers in addition to any other problems you might have insight to, which are going to be the best choice, aluminum or stainless? Thanks in advance for any help, I'd like to be back on the lake sooner than later.
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