So I changed the oil on the Monte. Let it run for about a minute and I revved it up to about 2,500 rpm when I suddenly heard a ticking sound. Specs: Iron 350 w/vortec heads, flat tappet cam and lifters. Ceramic coated Flo Tech headers, split lock header bolts, 2.5 exhaust with high flow cats. Oil: Amsoil Z-Rod 10w-30 Here is a quick video I made: It's not real pronounced in the video. I don't believe it's on engine sound because it's more the less coming from under the car and radiating out. I replaced the collector gastkers in the spring. As you can see the flanges look a little warped. Also the headers were installed in 2011 with heavy duty gaskets and not touched since. I've noticed they've slowly gotten louder. Maybe they need to be tightened? Any thoughts would be appreciated.