Hot start problem, Checking opinions before I buy a new battery Options

[Highland]

My car starts easily when cold, but hot it has been a struggle. I put a variable resistor on the CHT as an experiment without success. Engine's not even catching.

Plugs look good, 123 distributor, blue coil, valves adjusted, runs fantastic once started.

I am using a 2 year old motorcycle AGM battery(which has been working prior to 123 distributor install). Open voltage measures at 12.6V.

I stuck a lead on the coil while cranking and voltage drops to around 10V and will bounce down to 0 occasionally if I crank for more than a few seconds. With ignition only the coil is at about 12.3V.

The blue coil is an NOS coil that I had. It's probably over 30 years old but resistance is good when cold. I did not think to measure the resistance hot, but would it make a difference? Does the insulation breakdown over time even if resistance is good?

Thinking my little battery doesn't have enough power to crank and fire the coil. Any opinions? Cranking is strong.

[emerygt350]

Cold start has a few main bits. In socal temps the cold start valve gives a quick burst, and the AAR is open increasing idle speed. During this time the throttle switch is telling the computer the car is on the idle circuit since the throttle should be closed and it will be taking mixture info from the knob on the ecu and the cht, which on a stock 2.0 should have the resistor to make up for the 1.7 ecu used in 73. Fuel pressure is static on djet. The dizzy tells it when to fire, and the ecu, using the mps and the cht tell it how long to fire.

Now, in your case I would check to see what year ecu you have. I would also verify your injectors are stock or not. Since you have a bigger displacement you may have something else.