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So there are 2 alternators, same manufacturer, same case. One is 55 amps, one is 70. The only other difference between the two is the connector on the voltage regulator (3 pin vs. 4 pin). Can one regulator be substituted for the other safely?


The manufacturer and case may be the same, Main difference is the number wraps or turns of wire on the rotor and or windings of the alternator. just swapping the lower rated regualtor into the higher amp alternator may work for a time but IMO you will blow that regualtor out when reaching the higher output of the other alternator. They may look the same on the outside but the guts are different.

I would recommend you sick with the regulator thats in the alternator and adapt your harness or plug like Frank said.

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