Adjustable voltage regulator...how to adjust?

You may be right about needing s new alternator Mine runs 12.8 at idle with lights on, electric fans, Mallory 6AL and Fitech fuel injection. I am however running a chrome Powermaster 90 amp alternator. I have to turn my adjustment clockwise to increase the voltage
Yeah, its a Tuff stuff 140 amp, so i think i've just worn it out over the 10+ years of ownership. I'm sending it up to them in cleveland and they're going to go through it. Good company, quick turn around. Then maybe my adjustable regulator will function, or maybe it won't even be needed. I know my small crank pulley probably slows down the charging, but the car labors with 40 degrees of locked timing to start (after a day or racing and idling through the pits) , even with not hitting the ignition until its fully cranking.