Drove the trans am around the block today and half way around a horrible and really loud knocking sound started happening inconsistently when under throttle. I get back home and open the hood looking for something like a broken motor mount causing the engine to bang against stuff but nothing. Apparently one of the rocker nuts came off and allowed the exhaust rocker from cylinder two to bang around. Not sure how it came off since I have poly locks. Put the rocker back together and adjusted all the valves on this bank and it’s running perfectly fine now. Weird.