i went to look at a 77 elco, 474k(overhauled @ 255k) original 350 no mods other than Edelbrock air cleaner , i noticed when it idles it makes tapping sound the original owner died a week ago and his wife doesnt know anything about the car other than it has to go. is the engine on its last leg?

could be the valves need adjusting, could be loose bolts on the flywheel to torque converter, or a number of other things. but would'nt say the motor is going to go, but looking @ those numbers you posted. I would say its time for a rebuild anyways.

Does it go away when you push on the gas? if so, I could be like pete said the torque convert bolts. If it does't go away, it's probably a loose rocker. go ahead and check the valve lash on all of 'em when you take the valve cover off...

ill check that tomorrow.

i passed on it, trans slipped and the frame is bent.