Dual Battery System?

[RBuffordTJ]

I want to put a dual battery system in my 1984 (351W) Bronco XLT. I'm not sure where to start or if someone offers a kit for this type of upgrade. Anyone ever done this or have ideas?

Rick in Orlando

 

[lawman212]

&lt

I installed a two battery system in my 1972 K5 Blazer in the 80's. I just found a loction in the engine compartment and mounted the additional battery and Picked up some long battery cables and linked the (POS) to the (Neg) to join the battery. I then bolted the (NEG) cable to the block like the single battery and hooked up the (POS) as before and it worked fine. I quess you could do the same thing with a Bronco. I did it to my Blazer because I rebult a GM 511 Big Block out of a Cadi. and installed it in my blazer just to see if it would work. Had to have a tranny bult for it and cut the firewall to make it fit with custom engine mounts but it fit. It will work.

 

[bidibronco]

If you want it to work like it's supposed to (no saying lawmans way wont work right) you can go to a car audio place and they should sell a kit. If they're asking alot for the kit then you should be able to go to your local R.V. shop and pick the same thing up for maybe a little less.

 

[firelt90bronco]

I think you can get a kit, do it right.

 

[Shadow_D]

I may be wrong (just waking up) but if you go from neg on one to pos on the other doesn't that double the voltage to 24VDC?

 

[RBuffordTJ]

Cool, sounds like there are several ideas, I'm leaning towards looking for the kit because I want the power for several electronic add-on's I will be putting into the beast (hopefully soon). I just don't want the stuff to be too big of a drain.

 

[lawman212]

&lt

I did that because my Big Block would drag when I tried to start it. I added the secound battery linking them together (My Dads) idea to assist in starting. Well it worked great and never had a problem again with starting the engine. It didn't help with the gas problem associated with upgarding from a Chevy 350 to a GM 511 and having to change U-joints every 6mos. The big question is why do you need to add a second battery in a standard Bronco living in Orlando you don't have the Cold Winters to contend with that **** a Battery like up North?

A.J. Daytona Beach

 

[Seabronc]

I may be wrong (just waking up) but if you go from neg on one to pos on the other doesn't that double the voltage to 24VDC?

33117[/snapback]

​

Depending on how that was done it either shorts out the second battery or doubles the voltage to 24V. I'd venture a guess that he actually hooked the two POS terminals together.

The only time the extra battery will help you out is for extended operation of equipment with the engine off or when your alternator is not up to supplying the demand of the system, (which will eventually drain the battery). Normally the alternator supplies all the required demand when the engine is operating.

If demand while the engine is running is a concern, upgrade your alternator to a 3G 130, 160 or 200 Amp. In a properly designed electrical system, the battery is only in use when the engine is off. Some arrangements parallel the battery to give a longer engine off run time, but the danger is that you may run drain both batteries to a level that you can't start the truck. Some isolate one, (via a relay the way the Ford factory arrangement is), and feed the extra equipment like stereos and trailor equipment from it so you don't run down the main battery, (that guarantees that you have one to start the vehicle with). Others, have a manual isolation switch to prevent the same thing.

Ford factory dual battery arrangement.

 

[bluesman17]

Just get a red top or yellow top.