dedicated starting battery

[ncc74656]

ok so new plan then. does anyone have a recommendation on a battery charger/maintainer that i can wire into my block heater wiring and plug that in over the winter? say a 2-5A charger? for AGM

[ncc74656]

best i can tell is my radio is pulling almost dead on what my alt is producing (or slightly under) and thus the alt is not able to keep the batteries up over my short drives. i suppose maybe a 2nd alt is in order. i really thought a single 380A mechman would be able to handle a 3 way setup and one sub.

[SLYentist]

Alternators are not immediate power. It takes a moment (a lifetime in electronics time) for the regulator to notice to voltage drop, then kick in to keep the voltage up. A little light dim is expected even with a rock solid alternator setup, this is where having an oversized battery bank helps. I see you have a beefy bank, so maybe the voltage is ECU controlled?

[Tarball]

best i can tell is my radio is pulling almost dead on what my alt is producing (or slightly under) and thus the alt is not able to keep the batteries up over my short drives. i suppose maybe a 2nd alt is in order. i really thought a single 380A mechman would be able to handle a 3 way setup and one sub.

You're onto something here.

[Greasemonkey2014]

Ever think about completely isolating your car audio system? By running 2 alts. One attached to the starting battery and all stock electronics and the other alt on your agm batteries that power your sound system?