electronic ignition w/o a module?

You said:
"wires in the distributor go to the coil"

Would that be an orange wire & a black wire? If so, you probably have a Pertronix unit. The whole thing is a little black cube in the distributor.

If it is a pertronix, and both wires go to the coil... it is not installed correctly. A common problem, and it causes rough running & unstable timing.

Pertronix installation instructions

The module should get a full 12v on the orange wire. If it is wired to the coil, it is on the wrong side of the ballast resistor. They always start well, but will run poorly.

The other thing that can cause a lot of trouble with that unit is a poor fit between the rotor & the trigger. Some rotors allow the ring to "float" about 5 degrees - and so does your timing. Look for a rotor that fits the trapezoidal shape on the top of the ring closely. The BWD brand # D147P fits great.

B.