About 2 months ago, I had a 70 SS454 Chevelle towed to the shop with major engine damage. Engine had 2800 miles on a $7000.00 rebuild. Turns out the guy was super lucky. Chinese aluminum rocker arm failure. Axle pin worked out, broke the aluminum out of the tip end, dropped a valve, bent it like a pretzel, bent 2 push rods, shattered the valve guide, beat the hell out of the seat, sent metal fragments all around the one head. Fortunately, the engine was idling in a car show parking lot when it failed. I removed one head, rebuilt the head, put it back together along with a new set of Crower STEEL rocker arms. No major damage to the engine itself other than a few rat bites on the piston head, combustion chamber and intake port. Point of the post: Most of these Chinese rocker arms do NOT have a positive method for retaining the axle pin in the tip. They have a drilled clearance hole in one side and a tiny Knurled hole on the other end. The pin is inserted and a light press is applied to the pin to push it through the knurl in the aluminum. It's a ticking time bomb. There is no way the pins will stay put through millions of cycles. I inspected the rest of his rocker arms and 11 of the remaining 15 rocker arms had the pins moving out toward a similar fate. I know nothing about these Speedmaster rocker arms, but after looking them over, I couldn't find a single picture or text that mentioned how the pins are retained. There is no way I would use ANY aluminum rocker arm that doesn't have a positive retention method on the pin end. Jesel uses snap rings. Other less expensive designs swedge the pin on the outside. Pushing the pin through and hoping the termites hold it in there is non-starter for me.
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