I have a 1960 fresh 283 chevy in a 1932 Ford pickup. Ran like a champ for about 100 miles parked it next day dead #5 cyclinder. 600 cfm edelbrock manual choke,duel point mechanical advance distributer. 150 lbs compression on all cyclinders,have spark. I have checked everything I can think of at least 3 times.plugs ,run the lifters with it running,yes the rockers on #5 move. Ive been playing with cars for 30 years so I have checked and double checked all the usual things you look for ,no vacuum leaks,dwell right on timing right,etc,etc,any ideas or something else to check,if I cant find it soon guess I will have to pull the head,dont know what else to check.. Thanks..  

i would say.. use the timing light on all of the plug wires individually...  close to the cap and down by the plugs...  if your timing light clamp has a plastic body... you will have to separate the wires to get a true spark .

what you are looking for in multiple flashes instead of a nice even flashing..  multiple flashes would mean somewhere it is crossfiring...

the 5 and 7 wires are almost the same length... swap them... see if the problem moves to the #7...

turn the dist if there is room and reset the wires so they are correct again...


can you read the arcing patterns on the terminals inside the cap...   i have seen rotors that their tips are too short so the arc goes up instead of straight across.. this makes a  really hard to find misfire...   (they put the riveted on tip on backwards, round end out instead of the machined end...)