PEWTRESS, NATHAN JAMES III City/State: St George / UT PCF Number: 195766 Arrest Date: 19:22:00 02/01/18 Agency: St George Police Department RELEASED FROM CUSTODY
then you need a little more rpm to get the alternator to charge above the battery voltage. About 13.5 volts. The average alternator is now between 1,300 to 2,100 rpm. I set up an old 35 amp alternator to run off a 1/3 hp 1,750 rpm washing machine motor at a 1:1 belt ratio. Using the stock regulator would stall the 1/3hp motor. I put a large adjustable resister on the field connection of the alternator.
Most OEM crank pulleys are 6 in diameter while most OEM alternator pulleys are 2. This gives us a 3:1 ratio between the crank speed and the alternator speed. At an 800rpm engine idle speed the alternator is actually spinning to the tune of 2400rpm.