Major voltage drop when black/red wire from relay hooked up. Options

[tornik550]

I am confusing myself. I just installed my fresh 2.7 /6 rebuild. It started up last night and today within a second or so. I pulled a spark plug and I forgot to put it back in and tried to start the car- I immediately stopped and realized my stupid mistake. I put the plug back in and the car started however not as quickly. The car sat for a few hours and I tried to restart it and it didn't work. The starter turns and occasional a cylinder or two fires. I noticed that the voltage gauge was reading at 10volts. I checked my battery and it was fully charged. I started playing around with wires and I found if I remove the red/black wire from te coil- the voltage goes up to 12.8. Also- when the red/black wire from the relay panel is hooked up to the positive side of the coil- I hear an arcing type sound when I turn the key. The fuel pump sounds weak when the car is at 10 volts and therefore I only get about 0.5 psi fuel pressure which I would assume is at least partially why the engine is not firing.

I tried a different coil and there was no change. I do use a pertronix unit.

Any ideas of what might be going on?