fastlt1

iTrader: (4)

Am I over spinning the alternator. Fbody 25% under balancer. 04 escalade 145 amp alternator. Around 7200 rpm at shifts.

Finkledbody

You're under spinning the alternator. An Underdrive pulley spins the alternator slower so it produces fewer amps. People fix this by replacing the pulley with a larger one or change the alternator to a more powerful unit such as a 200+amp. Another option you can plug it into a battery tender after each use to keep the battery topped off so you don't over drain it.

Y2K_Frenzy

I’m new to GM, but in the olden days (the 90’s) people were putting under drive pulleys on their mustangs because they were relatively cheap & the magazine ads claimed a 25 horse gain.. The end result was dim headlights and a zero to two horse gain. They’d have to buy a higher amp alternator that was more expensive than the pulleys that didn’t yield any gains.
As for the OP, I think he put an under drive pulley on because he’s revving to 7k rpm and it’s possible that the alternator he is using wasn’t designed to spin that fast, so he wanted to slow it down. That being said I have no clue how fast his can spin. However, I’d let it ride unless I was having charging issues.

Finkledbody

7200*.25= 1800
7200-1800=5400rpm

probably not over spinning it 👍