How would this Alt. perform with underdrive pulleys?

Pentastarnut said
maybe i'm thinking wrong? i'm going to add vintage air and a small amp for rear speakers and a dual dash speaker set up AND the billet pulleys i have are underdrive. i figured a higher amp alt would maybe compensate for the underdrive pulleys :-k

The true answer to this is finding the actual engineering specs for SPECIFIC alternators.

I saw some charts here awhile back comparing SIMILAR same brand (Delco?) alternators of similar design and DIFFERENT amperage.

In at least one case, a LOWER output (45a?) alternator put out significantly more power at lower RPM than did the higher ??70-80A unit.