Help!!
I have just finished rebuilding a 454 for my '71. I am getting a strange noise from the #8 cylinder valves. It sounds like rocker noise but I have adusted them running and not running and I am convinced it is not the rockers. I listen to the rocker stud with a stethescope and I can still hear a clicking noise even after the rocker click has been adjusted out. The exhaust valve is the worst one. Some of the other valves have a slight noise but not like this. Some sound totaly normal. I also have detected a metalic ping on the #8 exhaust valve that occurs once or twice in succesion and then disappears for 30 seconds to 1 minute. I am guessing that I have a bad seat, spring, guide, valve...etc. I would like any diagnostic ideas you may have before I rip the head off. Thanks in advance for your help!!!

Sometimes a small exhaust leak can sound like a valve train noise.

I would agree with JoeKool...had the same sound and it was the exhaust gasket!Dont tear apart the motor like I did! Check it first.

does it make the sound with the valve cover off? i had the same problem. turned out to be the rocker was hiting the inside of the valve cover.

Guys,
Thanks for the responses. I tried again on Sunday to adjust the valves one more time. I have checked the exhaust for leaks and I have not been able to find any. I did this by listening with my stethescope. Is there a better way? As far as other diagnostics, I thought about bringing the piston up to TDC, presureizing the cyinder with air and removing the retainer/spring to inspect the valve. I can then move the valve by hand and check for anything that feels weird. What do loose valve seats or guides sound like when the engine is running? It seams that I can adjust out the sound but after reving a few times, it comes back.
I am confident that the rockers are not hitting the valve cover.
Thanks again for your input!