The Ford 4G develops 113 amperes @ 105c at a rotor speed of 1, 600 RPM. That is a ratio of 2.6 of crankshaft speed. My custom hydraulically driven 10 HP alternator test bench saw enough of them to become familar with their behavior. An hour's idling could serve to restore approx EIGHTY amp hours to a group 29-31 AGM battery. I fooled around with my LIfeline and the poor 50/120 MoPar Nippondenso was subjected to an 87 ampere charging rate.
A Magnatek can't walk and chew gum. The F105 Ford reg stll bats out 14.05 volts at an incredible 110c. Using the generator in a heads-up contest would be a joke. When the OP has a budget for a converter, then thought should be given to type and size. But a 10, 000 amp converter is only going to stuff around 30 amps into that single flooded battery at 13.6 voltsrating.
