I have not had issues with charging that could be related to high horsepower. It kinda sounds like the voltage regulator may be a bit over active, I think its internal on these newer alternators. Pop the alternator off and have a local auto parts store check it out. If you have a big stereo or something, I could see you getting a higher output alternator otherwise, I don't see a real need.
I would go through the alternator wiring and grounds to make sure everything is clean and secure. The alternator is internally regulated and there are only a couple wires going to it. Check the main alternator wire going to the battery, especially near the battery side, along with all connections and terminals. Clean up any corrosion you find and re-secure. Also, make sure the grounds going to the engine are good. Maybe one is coming loose, causing extra load on the alternator.
That is very unusual for a 3g alternator. The older 2g units were awful... I swear I was replacing them every 10k miles on my 88.
That is very unusual for a 3g alternator. The older 2g units were awful... I swear I was replacing them every 10k miles on my 88.