Hi guys. Looking for some ideas on my 65 289. I’ve been restoring the car over the past year, and in the process had the engine and transmission out for cleaning up and taking care of the engine compartment restoration. The engine ran well with no issues prior (other than a bad oil leak). I elected to just Overhaul rather than rebuild this one completely. I checked the main bearing clearances, which were within spec, replaced the timing chain, oil pump and pickup, gaskets, and cleaned/repainted the engine for re-installation. I reused the original pushrods and rocker arms, and kept them sorted to go back into the same bores. I primed the oil pump a few weeks ago, and Today was finally the day to test fire it. It took off quickly and idles well, but I have quite a loud knocking sound that gets louder on revving the engine. It sounds like it’s in the lifter valley area, but it’s difficult to tell. I re-adjusted the rocker arms, which did need a partial turn after heat cycling, but the noise is still there. It does not sound good, and I certainly wouldn’t be comfortable running it for any length of time like this. Just wondering if anyone has a quick idea of what I may be overlooking. My instinct says that perhaps a lifter went bad in the process of sitting dry outside the engine, and is now causing a loud tap on the cam. I’m going to try to post a short video to help you out. Thanks for your time.