[Bill OH]

I have used an analog voltmeter connected from one end to the other of a cable to find voltage drop. I have found that the battery must be connected direct to the motor from the plus terminal (6v positive ground) of te battery. Connecting the plus terminal of the battery to the firewall and at another point on the firewall to the engine promotes resistance - steel does not have the conductivity that copper possesses. And steel terminals on the battery cables also creat resistance - cut the steel terminals off and solder on copper terminals. And you might trying connecting the voltmeter to the positive terminal of the battery and the other lead of the voltmeter connected to the starter frame and then attempt to start motor. And try going from the negative battery terminal to the terminal bolt on the starter and again attempt to start engine. Observe the action of the voltmeter in the two test. And you can limit a test to just a section do the circuit. You should find the problem. Do not rely on crimped terminals - solder should be used.

Another thought - I put about 4 gaskets under the carbs and and blocked the heat risers and engine starts hot instantly, but this makes the car fair weather 50 degs F or above.