A dwell meter is nothing but a voltmeter with a different scale calibration. It reads an average of the voltage at the distributor side of the coil with the points open (battery voltage), and the points closed, (zero volts) For instance, a V-8 engine has a possible "points closed" dwell of 45 degrees of distributor roatation, and a desired setting of 66% dwell, or 30 degrees. If an analog voltmeter (the one with a needle, not a digital), reads 4 volts with the engine running, there is a dwell reading (points closed) of 30 degrees. (Assuming a battery voltage of 12 volts)
a 6-cylinder engine has 60 degrees distributor rotation between cam lobes, with a 66% reading of 40 degrees. Once again, an engine-running reading of 4 volts on a 12-volt system, 2V on a 6-volt, should be pretty close to the right point setting. Try it sometime!
Jerry
Last edited by Hotrod Lincoln; 03/02/2008 11:43 PM.
