Ah...then you are stressing over the output of the alternator too much. The current will be coming from the battery...it's capable of delivering 500 amps for short periods, 100 amps constant would be no problem...in your situation just think of the alternator as there to charge the battery...one of the 90 amp alternators in the stock case should be fine for your requirements...I suspect that you turn your radio down a bit before you park which should give the battery enough time to charge back up.

Going to two isolated systems would be for like if you are going to park somewhere and crank out a lot of power for a long time, or if you are going to be drawing the 200 amps from the system like I was doing. A 200 amp charging system just isn't necessary for a stereo drawing 90 amps...1000 watts does sound like a lot especially for stereo equipment, but I was running a 3,000 watt inverter and was plugging in a 1850 watt space heater to help defrost my windshield in the mornings.

I'm thinking that some of those setups are there just for looks. 3,000 watts of sound in a car could kill the driver and passengers, or at least render them deaf. I'm a musician and could cause extreme pain with my 100 Watt Fender Lead amp...my 100 Watt Marshall was just as bad, but could leave a smile on their faces. I just ordered a Marshall amp with dual 75 Watt channels for a total bridged output of 150 Watts. I've pulled these sized amps out onto my balcony and had kids 1 mile away ride their bikes over to make song requests. Placing the speakers 5 feet away and turning it all the way up would melt brains...and that's just 150 Watts!

 

I take it this reference is to Durango Boy?

 

Yeah it was. In responce, yes, for short periods a 100 amp draw froma stereo would not be bad. But, when I drive it I DRIVE it, and the stereo stays on. Not to mention I will have fans and lights drawing on the system. That will not only run a battery down fast...it damages a battery faster. I replace the stock battery in my Durango once a year because the stereo pulls more than the 'High Output Alt' can keep up with. It drains, and recharges when the stereo is turned down. Do that too many times, and you cut yiour battery life down five times.

I have an Optima ready to go in, and probably a second one before I'm done. The other thing I want to consider is upgrade. The system is fairly small by all accounts. High wattage, but small. Knowing me, I like to upgrade. While I only have 2 10" subs now, and 2 sets of components...that may turn into to 12" subs in a year, and I want a strudy electrical system in place now while I'm doing all the work. I'ts just me being prepared.

Besides...the alts will have a MUCH longer shelf life than the batteries, and with a setup like I'm planning , they will not have to work as hard. They will last longer, and save me from having to replace a battery after a year because it drained and charged too many times.

I'm sure I want to do it...I just want to do it right.