I have a 64 Belvedere in the shop right now. Customer reported a miss under acceleration.
I did check the ignition and fuel, no obvious problems. Under accelaration it pops out of the exhaust and I can hear a slight knocking noise which I would locate somewhere in the rear of the engine, but not from the rockers. The noise dissapears when the engine is above 1500rpm.
Could a wiped cam cause the missfire? Edit: collapsed lifter would cause the same symptoms, correct?
Thanks,
Frank

plugs/wires/timing/rotor phasing/cap crossfire/rotor clearance. wiped cam w act up all the time. For fuel: eng mods not stated but any poss of fuel starvation & in all gears or high gear, what vac (PV open or closed). Might T a vac gauge to the carb inlet & tape it to the windshield & (re)test it (most have a psi side) & find directly if fuel starvation or you already have this covered. A good basic compression test will cover the long block EDIT forgot a very imp one, dist pickup gap/plate integrity (no looseness etc)/shaft side clearance tho this is rare & might pull the can thru it's travel w a Mityvac if vac adv is used & check the gap ch if any suspicions the gap may b too large

checked compression last night: all cylinder are at about 145psi when cranked cold, except #4. This cylinder goes up to about 120psi when I first hit the starter, on second try no compression at all. Leak down test showed more then 80% loss. Intresting is that the cylinder will seal after a couple of minutes with the leak down tester hooked up. Looks like a ring sealing issue. I will pull the head tonight, then I know more...