Upgraded CS130 Alternator is Pushing 18+ Volts - Battery, Regulator or Pinout?

[jamcomanche]

I originally had a 74 amp CS130 in my 87 2.5 and the bearing went out. Because I have some power fluctuations with lighting and an AMP installed, I decided to upgrate to a 105 amp 8137-3N from WAI Global. 

 

After I installed it and started up the engine, the voltage on my dash immediately went into the red at or above 18 volts. After a couple of seconds, it started cutting power repeatedly so I shut it off. I disconnected the output cable from the alternator and the connector and started her again to make sure it wasnt unrelated, and it read around 10-11v on my gauge. 

 

I started a return since I assume it's a bad voltage regulator in the alternator if it's pushing out that much voltage, but then I started thinking about what else could possibly be causing it. I ordered a pigtail replacement, which ended up being a 4-wire so I needed to figure out how to wire it up. Then I started looking at wiring threads and the pinout for the 8137-3N. 

 

My previous alternator only used the 2 middle terminals on the connector ( L and I/F pins ). When I look at threads about wiring up the CS130 with a 2-pin connection (this one for example), 99% of what I found said it should be using either S+I or S+L pins. 

 

Is there any reason I would need to change from the L+I connections to the S+I or S+L connection? Would that possibly cause the high voltage output? Or am I right in thinking it's just a bad regulator in the alt? 

 

Any help with this will also help me figure out the right way to wire in the new connector. Thanks!