Im going to be running my battery in the back of my car this summer and i was wondering if anyone else has moved there battery from the front to the back. How did you wire it up? Thanks

 

Depends if you want it NHRA legal or not. Any battery not in the stock location must have a master cutoff switch at the rear. The switch must be wired into the positive side of the battery and must kill the engine and all electrical in the car when turned off.

If you never go to the dragstrip then just connect the negative to the frame and run the positive cable to the starter/alternator.

 

I've heard about the cut-off switch turning off the battery, but shuting down the car? How is that done?

 

When the switch is turned off the ignition system and charging system has to by wired so that it disconnects the power to the ignition system and from the alternator. The alternator will still provide power to the rest of the system if just the battery is disconnected, so it must also be disconnected. You need to use some relays.

It's a safety requirement. If for any reason you should crash, the safety crew can simply turn off the master switch and all the electrical will shut down.

 

You can do it without relays too. Just run a 10 gauge wire from the alternator to the battery side of the disconnect. My page has pictures of my install of the battery in back including modifing the cut off switch to a push-pull style (it must be a push off to be NHRA legal). Also, here is a schematic from Sho-Gun on the wiring

www.koolmeister.com/bat_wire_dia.jpg

Miles

 

Interesting. I may have to do some rewiring to simplify things.

One thing I don't see in that schematic is the main start/stop curcuit. ie. turning on a power switch in the car then starting it. Turning off the power switch in the car to kill the engine. I suppose a simple on/off switch installed in that wire marked 4 gauge wire coming off the main shut off would do it. That wire feeds the rest of the car with power.

Actually the 10 gauge wire from the bulkhead connector to the MSD box would be better. That way the car can be shut off and still provide power to the electric water pump and fan.

I see another problem with that curcuit. They assume you use a one wire alternator that doesn't use a field curcuit. A typical 10SI alternator has 3 wires. A large red wire connected directly to the battery. A dual wire plug with a red and brown wire. The red wire can be looped to the battery post on the alternator however the brown wire needs a power source for charging. It's usually hooked into the in-car power switch. When power is turned off in the car or at the master switch, this curcuit must be disconnected from the battery so that the alternator doesn't keep feeding the ignition curcuit with power and keep the engine running.

I'm going to have to go over my car's wiring again to see what changes I can make. I only have 4 months before the 2002 season starts.

 

I used one guage welding wire. I found it at a local welding shop for $1.23 / foot. It took me 25 feet total. I used an optima battery and the moroso blue box with hardware. It's mounted in the rear well because it wont fit in the compartments. Ground to the rear bumper mounts, making sure to sand off to bare metal and coat with grease afterwords. The postitive cable runs through a bushing or bulkhead thru the body and then tracks to the starter with the fuel rails and then over the transmission. I was extra cautious and used wire loom for rubbing and "zip" ties for attaching the cable. I used the summit rear cutoff switch and mounted that in the center panel of my firebird tail lights. Use a dremel tool to cut the first inside layer of plastic. I used a rubber washer and some weatherstrip glue to give it a finished look. Five dollars at the local sign shop also for some custom gold on and off stickers. The install is very clean and seamless.