[J-Mac]

Originally Posted by dtw

It is pretty easy when doing a DIY rebuild to improperly install the chain ramps. They can be fiddly.

In the meantime, pull your oil filter and cut it apart, and take a look for rod bearing material in the pleats of the filter (you'll be seeing more of that black plastic material too). Was the sound a very regular rhythmic knock, or more like dropping a spoon into a garbage disposal kind of random and chaotic?

The OP rebuild was done by a race shop, so I guess they knew what they were doing.

And the sound was rhythmical not random. Would metal particles make it to the filter before the engine oil drain plug? I'll pull that tomorrow and check it out.

Thanks again for all the suggestions.