One wire alternator

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Doosterfy

Doosterfy

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I'm building a 440 Duster. Its a street strip car and the battery has been relocated to the trunk. I'm redoing the under hood wiring harness also and would like to clean things up. I'm looking at possibly buying a Tuff Stuff one wire 100 amp alternator from Summit and losing the factory voltage regulator altogether. The TS alternator is a Mopar square back style. Has anyone gone with this setup? Any issues or regrets? Advice, etc. I know I have to run the output from the alt to the hot side of the battery disconnect or the positive post of the battery and It would really clean things up to have one simple wire go from the alt to the rear of the car.
 
I've said this before------I don't like this philosophy and I don't believe it actually meets NHRA rules, which has words to the effect "must kill all power."

The EASY way to get around this is to buy a FOUR terminal disconnect, made by Cole Hearsey and others. The correct term is "two pole" switch, and these have two large (disconnect) terminals, and two smaller terminals for a control circuit.

All you need to is ground one of the small terminals, and run just one no14 up front in addition to your main cable. Use this no 14 wire to ground the coil on one side of a quality relay or "continuous duty" solenoid, and they use your ignition switch to power the high side of the coil. The alternator output can now be hooked to the main cable up front, at starter relay, etc.

Use the contacts to break your ignition run circuit, and if you have an MSD, this might be even easier because of their switching method.
 
67Dart273 said:
I've said this before------I don't like this philosophy and I don't believe it actually meets NHRA rules, which has words to the effect "must kill all power."

The EASY way to get around this is to buy a FOUR terminal disconnect, made by Cole Hearsey and others. The correct term is "two pole" switch, and these have two large (disconnect) terminals, and two smaller terminals for a control circuit.

All you need to is ground one of the small terminals, and run just one no14 up front in addition to your main cable. Use this no 14 wire to ground the coil on one side of a quality relay or "continuous duty" solenoid, and they use your ignition switch to power the high side of the coil. The alternator output can now be hooked to the main cable up front, at starter relay, etc.

Use the contacts to break your ignition run circuit, and if you have an MSD, this might be even easier because of their switching method.
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Thanks for the advice. What is it about this method you don't like. Is it the long wire and voltage drop, or the risk off a short? I've used this setup before and had no problems. And I assume you mean this for any alternator, not just a one wire alt.
 
It leaves what amounts to a fairly dangerous live cable "hot" and I don't believe it actually meets the intent of the NHRA rules. I don't have them in front of me, but I believe I remember something on the order of "kills all power" referring to the disconnect.

And yes, you can use this method on either conventional or one-wire systems.
 
67Dart273 said:
It leaves what amounts to a fairly dangerous live cable "hot" and I don't believe it actually meets the intent of the NHRA rules. I don't have them in front of me, but I believe I remember something on the order of "kills all power" referring to the disconnect.

And yes, you can use this method on either conventional or one-wire systems.
Click to expand...

I'm actually suprised you haven't addressed the "one-wire" alternator itself. The rest of this is killer dead nuts on.
 
I have a one wire 60 amp alternator on my 75 Duster, and my battery is also in the trunk. I added a 60 amp fuse at the battery for the alternator, just incase of a short in the charging circuit. I used a #6 high temperature wire between alternator and the fuse in the trunk. I also added a Ford style starter solenoid to open the hot wire at the battery when the ignition is off, or the kill switch was opened. The solenoid I used could be replaced with a two pole kill switch as stated above. I was able to redo all wires from the engine bay and hide them for a clean look. I agree that all power needs to be off or contained within the battery if you open the kill switch.
 
LETSRACE said:
I have a one wire 60 amp alternator on my 75 Duster, and my battery is also in the trunk. I added a 60 amp fuse at the battery for the alternator, just incase of a short in the charging circuit. I used a #6 high temperature wire between alternator and the fuse in the trunk. I also added a Ford style starter solenoid to open the hot wire at the battery when the ignition is off, or the kill switch was opened. The solenoid I used could be replaced with a two pole kill switch as stated above. I was able to redo all wires from the engine bay and hide them for a clean look. I agree that all power needs to be off or contained within the battery if you open the kill switch.
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OK, so what you guys are saying is that if the wire, or any wire connecting the battery in the trunk to the engine bay still has voltage when the disconnect is off/open, It is dangerous and does not meet NHRA rules. I'm a little bit confused as to why there is a need for a relay in the circuit. If one was to go with the Cole Hersey four pole disconnect and when it is open/off the main battery cable and the charging wire are disconnected from the engine bay, would this not be effective and meet the rule? I was going to fuse the charging wire at both the battery and the alternator also for safety. As far as the one wire alternator, no noe has had problems from what I see. I wonder if any companies offer a kit to convert a Chrysler alternator myself. I have lots of them kicking around my garage. Thnks alot guys, I appreciate your help.
 
OK here's the thing:

You cannot use the small contacts in the Cole Hearse to break the charging wire directly, as they won't carry the current, depending on how large your alternator is.

With the 4 terminal switch there is no need for a separate charging wire back to the rear. You can just tie it in up front to the main cable.

The reason for the relay is that you MUST break the ignition circuit. Remember the old wives tale, where you can SUPPOSEDLY check an alternator by disconnecting the battery on a running engine? Same thing here. If you wreck your car, and it's still running, the rescue crew cannot kill the engine by pulling the disconnect. It will still run off the alternator.

The other thing gets into "strategy" I guess. Some guys don't like the idea of having a huge big main cable that is hot anytime the disconnect is on. So this is where the Ford solenoid in the trunk thing comes in---they run a no6 or so wire for charging and ignition, etc, and then use a Ford relay to only fire up the main starting cable during cranking. But this becomes even more complicated, as you STILL need to separate ignition from the alternator in order to insure that the engine dies when the disconnect is pulled.
 
LETSRACE said:
I have a one wire 60 amp alternator on my 75 Duster, and my battery is also in the trunk. I added a 60 amp fuse at the battery for the alternator, just incase of a short in the charging circuit. I used a #6 high temperature wire between alternator and the fuse in the trunk. I also added a Ford style starter solenoid to open the hot wire at the battery when the ignition is off, or the kill switch was opened. The solenoid I used could be replaced with a two pole kill switch as stated above. I was able to redo all wires from the engine bay and hide them for a clean look. I agree that all power needs to be off or contained within the battery if you open the kill switch.
Click to expand...
I'm having second thoughts about using a 100 amp alternator. I'm running a mechanical fuel pump, and no stereo or anything else that will draw alot of amps. The biggest draw will probly be the head lights and an electric fan. I'm running an MSD distributor and will be purchasing an MSD ignition box which I'm not sure how many amps it draws. Where did you get a 60 amp one wire alternator? Is it a Mopar unit, or a GM, or what?
 
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