Ticking after warm up.
Haven't posted in awhile, got my car done last year finally, been running great. Only thing i had a temp sensor go bad and cook my plugs. Replaced sensor and new plugs and been running great. Anyways have noticed if i let car idle for awhile, it will develop a tick that gets pretty loud. If i rev it up it will go away, if i drive it, it will go away. I do have a constant light ticking while driving but i just chalk that up as being an ls. Anyways, its driver side. Replaced header gasket, no help, oil is good and fresh, car runs amazing. Im just lost. I do have a teeny tiny exhaust leak at collector just wouldn't think it would be that. One thing that makes me nervous is the shop that built it put way to short of push rods in. Got that fixed pretty soon after running it so idk if that could have anything to do with it. Any help much appreciated. Thanks in advance.