Hi,
Have started to take care of old (small) irritation problem on my white 64 dodge 330.
When start the car it have been a noice from the starter or some other electrical device.
Yesterday we start measure using an oscilloscope. We found a very big lack on voltage when start the car.
When we had measuring some spots the resultate was about 6 Volts to the starter.
After checking the voltage over starter relay we found that the realy close and open hole time under the starting of engine (that making the noice).

We took the battery and attach it directly at the starter and ground/negative direct on engine and the engine started great and without any bad sounds from start relay or starter.

For info the battery is new and are located in the trunk. The positive cable is 1 gauge and negative is ground in trunk floor (on engine the ground is attach to the firewall).

Its a lack of 2 V ground in chassie when we measured. Adding the lack of voltage in the postive cable and the voltage lack in battery when start/crank the car all that resulting 6 V at the starter.

I'm about route a good ground/negative cable from battery in trunk to the engine.

Strange, almost same battery setup in my 65 coronet havent any problem.

Stay cool.