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wiring for rear mount battery.. what would you do?

907 Views 4 Replies 4 Participants Last post by  PonyDoc
Well there's a few factors to concider here. First of all I will be using a 3g alternator, which is 130 A. So i need a thick cable for that.

To be race legal it has to have an off/on switch on the rear of the car, this would require running the alt. line to the back. Should I do this just in case i decide to go race legal?

Also, many people recommend putting the starter solonoid in the trunk and running just a fat cable for the starter and then a much smaller one for the accessories and such. Should I do this? How should i route the wires?

Thanks. I can't make up my mind how to do this.
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Most people over look the 1 thing that's most important... a really good ground. Leave the solonoid where it is & run a big welding cable for it, use a high-quality connector & solder it! Battery has to have 3/8" hold downs & really should be in a good case. Also, leave the alternator as it is & find someone(I have one but don't remember the man. name) that makes a diode to shut down the alt. when the engine is off, it's NHRA legal. Make sure to route the wires away from heat & suspension & use adale clamps to make it pretty.
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Although I've run the race car for years with the solenoid on the frame rail near the starter, I do see the wisdom in locating the solenoid to the trunk, especially in a street car.

Yes, if you are going to race the car, you'll have to demonstrate the emergency shut off will indeed kill the entire electrical system, which won't happen as long as the alternator is still hot (and the engine is running). I've never dealt with this matter (no alternator) but would assume you could either run the field wire to the back or install a solenoid up front for it, which would be controlled by the shut-off. The rule book likely has the specifics (I don't have a current one).

Just be sure to protect your cables from chafing and impingment by chassis parts...some guys put them in pvc or something like that (I don't)...

Hope that helps!
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I would leave the solenoid in the front. Hey wait, I did, LOL. It comes in handy for bumping the motor over when adjusting the valve lash or for hooking up a timing light. Get the Summit battery kit and a Moroso on/off switch. They are both NHRA legal. Run a 6 or 8 gauge wire with your big positive. Theres a threaded hole in the frame rail under the right rear side that is perfect for the short ground cable. The big red cable goes up over the fender well and down inside the passenger side rocker panel and up behind the kick panel and out which ever hole up under the dash you prefer to use. You can drill holes in the fender well where the inner and outer are put together for tie wrapping the cable. It isn't going any where like that. Well, this is how I did mine but you don't have to do yours that way. I had to grind my spare tire hook bracket thing off for the tray to sit level.

Oh. Just put your alternator charge up wire on the battery side of your kill switch.
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We used the welding cable, as suggested, and wrapped it with elec tape after using welding rods alongside the cable, to stiffen it. The "0" gauge pulls the current very well and you can use brackets along the frame rail to attach it. The stiff cable tucks up very nicely.
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