two batteries or upgrade alternator?

Alpine Guy: Regardless of the load you can hook to the alt, you wouldn't maybe run a DMM over it would ya? See what your idle voltage is? Irragi alts seem to fit everything and they're not expensive at all.. I've had really bad luck finding alts that don't drop to like 9v or something like that at idle.. the only solutions I've come across are like $1000, mod-requiring Stinger alts.. which are obviously prohibitive. Nava: If the customer proves dis-interested in the outlay an HO alternator would provide, perhaps a secondary DC power source much closer to the amps might do as much to alleviate the dimming headlights.. "I'm finished!" - Daniel Plainview

At idle with no load it charges at 14.9V, I would imagine that would change a few points if a load was attached.2003 Chevy Avalanche,Eclipse CD7000,Morel Elate 5,Adire Extremis,Alpine PDX-4.150, 15" TC-3000, 2 Alpine PDX-1.1000, 470Amp HO Alt.