I have a knocking noise coming from my 383 stroker..just started..it's not that loud and if I rev it up I can't really hear it then when just idling again u can hardly hear it..not sure if this is a rod knock I'm hearing and hopefully not wanting to deal with a spun bearing..my oil level is up there and I'm gonna change today..to check for any metal flaking..I know it has roller rockers and I don't believe it's coming from up top although the engine is kinda loud and sometimes you can't hear it all. I just didn't want to make the problem any worse..any suggestions on how to narrow this down? And what type and weight of oil..I should be running?..or any other suggestions would be greatly appreciated..ty..Stevel