For my engine we went with a 150 Amp Powermaster alternator… a billet aluminum alternator mount, and a 3-1/2” diameter billet aluminum 6 rib drive pulley.
The stock pulley on the Powermaster alternator was 2” diameter. The engine builder changed the pulley from 2” diameter to 3-1/2” diameter so the alternator would run at the correct speed when I am running higher RPM’s on the track. He also provided a 2” diameter pulley and a smaller diameter serpentine belt set up for street only use.
So far I have run the 3-1/2” diameter on the track and on the street with no issues. I did notice that when I’m in traffic on hot days with the electric fan running full time, the battery voltage drops slightly. Under normal driving conditions it's fine.
Billet aluminum bracket with alternator mounted high on passenger side of engine
Here is a shot of the stock 2" diameter pulley in comparison to the 3-1/2" pulley.
