my Mustang,, shown below in my sig, has a rattling noise near the top of the heads, on the right side of the engine. i was just wondering if they were cam bearings or main bearings? my dad said they could be either, i just wanted to be sure so i could have them replaced when i replace the top end of my engine with P&P heads/intake and a new cam. is there a way to find out if it is one of either?

 

replace the mains or cam bearings and if it doesn't stop you'll know it was the other one lol, jokin thats probably not a good idea.