Yes cams are hardwelded. The cam supplier now wants me to send in a set of rockers to be hardwelded and say this will make the set up work. I understand this will make the rockers more resilient but if it it really a lubrication/oil retention issue then it is still not a good design and I would be better off finding different cams (not hardwelded), The odd shape of the worn cam lobe is puzzling; it is not round any more, but faceted. Also I agree it is not unlikely that the completely destroyed DP1120 rocker may be low quality. There was only that single one marked withDP1120 of the twelve installed, and it was the only one to fail in such a spectacular way. It may be a point that the same DP1120 rocker had survived without any damage in a previous build with stock cast cams.
Quote:
Originally Posted by Henry Schmidt
I don't know what oil he was running but I already posted the spring rate.
The issue isn't so much the oil weight but the capacity for the rocker pad surface to trap oil.
Chill casting allows for the greatest oil retention capacity in a cast product and if the cams are chill cast (I assume they are) and the rockers are not, the rocker surface will most likely be compromised.
Now at some point the OP posted that the cams were hard welded and that is an entirely different kettle of fish. Hard welding will remover any surface porosity and the only way for the rocker to survive is to have a reliably hard surface. Relative to the cam that is.
My guess in this situation is simply poor quality rockers (we are seeing more every day) or low quality rebuilding technique.
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