Hmmm, I suppose that may could be the trouble. After I rule everything else out I will throw the old lifters in and re-assemble with cheapy gaskets. If noise is gone that was it.

Bad,
That sounds like it could easily be a rod bearing too. Have you cut the filter open to see if there is any bearing material in it ? Rod bearings usually will not affect oil pressure when they first start to fail. Wrist pins or a loose skirt will usually not start all of a sudden, even though it can happen.
Did your machine shop install seats in the heads ? I have done 4 pair of 502 heads this spring and none of them needed seats, they were about the hardest material I have ever seen. Could be a valve sticking when hot, but you probably should have been able to pick that up with the scope on the valve cover.

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

What ever it is PLEASE let us know.

That knocking is money trying to get out of your wallet.

My bet is a valve guide has gone bad, if that is the case, be sure to replace that valve also, because they get to rocking around and are prone to break off a piece of the valve or the whole mushroom, and that gets real ugly.

Head is at the machine shop now. Never heard a noise that could not be determined after a few beers. Those that heard it were split between rod, lifter, skirt, broke ring and where is the beer. I will find it...

The cooler that is.

BadDog...any updates on this problem?

Sounds like you are about to spin a rod bearing.

Yup, caught it just in time. The rod bearing was spun but still there. Part of the bearing was hanging out and hitting as the crank turned. Getting new Eagle I beam rods and turning crank. Upgrading to forged pistons while it is down. Sucks that this had to happen in the spring. Should have took it out over the winter but everything seemed fine last fall. Good oil pressure and no noise.