Hello all got a question.
I bought a rebuilt 440 and recently installed and got it running. it is a bit of a mystery motor but I do know it has 10.5:1 compression and a 488 lift Elgin cam. All internals looked good with assembly lube etc.
It's got about 100 miles on it. When it idles it has a definite clatter to it almost like a diesel motor. Oil pressure is 50 lbs hot at idle and it runs at 180 degrees or less. Runs good overall.
The rockers are non adjustible stock type. Could the pushrods be too short? The rockers have some considerable side to side movement when the vavle is unloaded. Timing is 10 degrees Btdc. What else could cause this type of noise?

Thanks, let me know if any other info would be helpful.