Should I upgrade my alternator?

[burgundy]

My setup(once it's complete):

Front: Infinity Kappa 62.9l

Rear: Infinity Kappa 693.9l

Trunk: RF (2)T215d4

Power: T400.4 for the frontstage

(2)T1000.1BDCP for the subs

I have an upgraded battery under the hood, and a high output AGM battery in the trunk. The alternator is stock.

My setup hasn't been completed yet. But I noticed while I was running what I currently have installed(which is the same speakers but on a zxi80.4, but a couple GPV 12d4s for subs, and only one of the T1000s) the lights are starting to dim.

I also believe that the shop I went to might have messed up and consequently killed one of my batteries. The rear battery is typically grounded in the rear and the pos runs to the pos in the front. I had no problems with that setup previously. But now this shop has the positive running to battery relay. I don't know if this makes a difference or not.

So I basically need to figure out if I need a better alternator and whether or not I should adjust my wire setup.

Click to read more...

 

[naughtyca 10+ year member]

do you have a volt meter to see what voltage you have?

 

[burgundy]

I do not. But regardless of voltage, shouldn't the alternator be upgraded to support 2 batteries? Also is a capacitor necessary with 2 batteries?

 

[LosIsATool 5,000+ posts]

Caps are never necessary, at least the ones you buy from a shop. Yes you need to upgrade the alternator. You are going to be pulling a lot of cuurent with those amps. Atleast a 220 amp, bigger if possible. 270 amp and you wont need a rear battery.

 

[Full Tilt 10+ year member]

I do not. But regardless of voltage, shouldn't the alternator be upgraded to support 2 batteries?

It's not designed to. Your vehicle's alternator is only designed to maintain 1 battery's voltage - the one under your hood. It's going to affect charging when you hook it up to two batteries, but people do it regardless. In fact, I'm going to. However, even if you're only dipping into the 13s, dimming can still be a problem. Voltage drops affect all vehicles differently, and some is hard to get rid of without even the best electrical system. My advice - figure out how low your voltage is falling, and we'll be able to help you a little better.