I just completed a complete engine rebuild on a 1967 comet capri. I did some modifications, .030 bore, crank ground, rebuilt heads, 4 barrel intake, headers, and an MDS coil. When I first turned the engine over for the first time I had lots of spark. The timming was out 180 so I disconectes the coil wires, and pulled the distributorto corrected it. When I turned the engine over there was no spark. Since then I have replaced the coil with a stock coil, points and condenser. Still no spark. I tested my ignition wire, it is at 12 volts on the positive side of the coil. I also have 12 volts at the negative post of the coil. There is also 12 volts at the wirethat connects to thepoints.I have checked the grounds to the block and firewall, they are fine. Now I seem to have a very weak spark sometimes and no spark other times. I have started to pull what little hair I have left so any help would be greatly appreciated. One other thing I'm worried about is I've turned the engine over for a total of about 4 or 5 minutes trying to fix this problem, my concern is my cam and lifter break in, am I still ok? HELP!!!

 

Sounds very strange?
I would suggest also replacing the Cap & Rotor too.
As for the cam & lifters condition...I have no idea