2000 Chevy Corvette Tapping coming from the engine?

Hello! I own a 2000 Chevy Corvette Coupe with 26,600/mi. When I turn on my engine, I notice that there's a light tapping coming from the engine. I guess the easiest way for me to explain it, is that the engine somewhat sounds the same as that of a School Bus engine (not as loud, but it definitely reminds me of that). The engine oil is new. I've heard that it could be a loose rocker arm, but i've been able to rule that out. Another person said it could be a dirt issue within the engine.I'm just not sure, but it's a light tapping while the engine is cold - somewhat cold (cold start to about 160 degrees). I hope i've given enough information. It's the stock LS1 5.7L V8 engine.