6 volt or 12 volt

[Standing Elk]

Ok, just got my "new to me" 30 coupe home and am starting to sort some things out on it. What are your opinions on doing a 6 to 12 volt conversion. This car had a non working alternator on it and I have some doubts about the health of the battery. I am anticipating having to replace both the battery and the alternator or generator whether I go 6V or 12V. I see Mac's sells a 6 to 12 volt conversion kit that includes a new 12 volt alternator, light bulbs, rectifier, new 12 volt coil, and a starter field coil. Has anyone used one of these kits from Mac'c? It appears to include everything needed to do a complete conversion. Also looks like nothing would be altered to the point of not being able to go back to 6V if you wanted to. Anyway just curious as what opinions I could get. Thanks

[BILL WILLIAMSON]

6 Volt stock system is VERY sufficient! DON'T follow the "FADS"!-- BE your "OWN" Man!
Bill W.

[springerpete]

I have had no problem with 6 v for almost 10 years. If your 6 v system is lacking then you have other issues you need to identify and fix. Stay with what FoMoCo produced.

[steve s]

You will discover that there are strong feelings on every side of every Model A related issue. Decide what your "concept" is for your car and do what it takes. In this case, if maximum authenticity lights your fire, stick with 6 volts--many people are happy with that. If the APPEARANCE of authenticity is good enough for you, then you nave more options, including 6V voltage regulators either built into the cutout can or hidden in the generator, or an alternator built into a generator case. If reliability, convenience for use with modern accessories, and peace of mind is a priority, then join the rest of the world that has switched to 12 V, negative ground: there were good reasons for going to 12V (by contrast, negative ground was apparently just a technical toss-up but done for uniformity's sake.) I've done the switch but not with a kit. The kit you describe sounds complete except for a load resistor to put in series with the horn. I don't know what the rectifier would be needed for.

Eventually, you'll have to confront similar issues, like detergent oil, thermostat, fuses, antifreeze, sealed water pump bearings, shortened Pitman arm, and on and on.

Have fun!

Steve

[Bob C]

You may want to do some research on Macs shipping charges, customer service,
and parts quality. There are plenty of good vendors.

Bob

[Synchro909]

Sponsored Links (Register now to hide all advertisements)

Originally Posted by bob c

you may want to do some research on macs shipping charges, customer service,
and parts quality. There are plenty of good venders.

Bob

x2!

[BillCNC]

Originally Posted by Bob C

You may want to do some research on Macs shipping charges, customer service,
and parts quality. There are plenty of good vendors.

Bob

Bob is correct, ...

X3

Regards
Bill

[160B]

Standing Elk

I installed a 6 volt positive ground alternator and left the rest original.

I looked at the kit and was surprised by the low cost $137.37

http://www.macsautoparts.com/ford_mo...rsion-kit.html

If you price out the items in the kit the total cost if you bought each item individually is around $335.01, so you save $200.00 by purchasing the kit???????????????

read post #5, #6 and #7

Kit Includes:
1 Alternator (A10000A12) $192.99
1 Starter Field Coil (A11081) $40.99
1 Coil (B6A-12029-B) $30.49
1 Ballast Resistor (A12001) $7.49
1 Horn Resistor / Voltage Reducer (A13802R) $27.49
1 Ammeter (A10850/30) $10.49
2 Headlight Bulbs (B13007E) $4.98
6 Dome, Dash, Cowl & Tail Light Bulbs (V13465D) $5.70
2 Stop Light Bulbs (V13465B) $1.90
1 Electric Wiper Resistor (V12873) $12.49

[marty in Ohio]

My six volt system has served me well for the 24 years that I have owned my '30 town sedan and apparently well for the 87 years that the car has around. But, as all have said, it's your choice.
Also, beware of Mac's.
Marty

[barkleydave]

This topic comes up often with same answers. Do what you like. Why did cars universally go to 12 Volt you ask? Answer: Smaller wire gauge for battery cables. Less amp draw for starter etc. Me personally I tour and have halogen headlights which are as bright as modern cars. I like the idea I can get a battery anywhere. (six volt not always that easy in a pinch) Can jump car with a modern 12 volt car. I can use 12 volt acc. if I whish. You reasons my differ or not matter at all. Fine Point show cars do not qualify for change. LOL

[Jim Brierley]

If you are going to run higher compression, and maybe other mods, go with the 12v system, for easier and quicker starting. Otherwise 6v is OK but do not use a stock generator if headlights or other mods have been made, it will not keep up and will throw solder if you try. I have used 12v since 1959 with no trouble. I also use the stock starter.

[ChetVL29]

I have a '29 Tudor that I want to swap to HC Head, touring cam. I appreciate the pros/cons of each, but think I'll upgrade to 12V. Thanks for the info guys

[MAG]

There is no need to change to 12 volts unless accessory installation demands it such as AC. If the conversion is made, in spite of comments made about converting the starter not necessary, it just is not true. I have had 5 come into my shop that the starter ring has been pushed off because of 6volt starter on a 12volt battery. Happened on my own car. Failing to convert the starter is like having a pet rattlesnake.....one day.

[Bob Bidonde]

I have been running 12V systems in both of my Model A's without any changes to their starter motors. If you opt for a 12V system, omit the starter changes.

[Patrick L.]

What are you going to do with the car ?

A conversion 'kit' is not needed. Anything needed is readily available, and, thats not much.
A generator and starter will work fine on 12V. [ To me, an alternator just isn't right]

That said, I find nothing wrong with 6 v. I just use a voltage regulator.

[Charlie Stephens]

You don't need a "new" ammeter, they are junk (at least al of the ones I have seen). Run a jumper wire across the two terminals at the back of the ammeter so some of the current goes through the jumper and some through the ammeter. You may be able to accomplish this at the junction box on the firewall depending on your wiring. You may want to run a wire in parallel to the one from the cutout and hook it to the other side of the ammeter. Use the same gauge wire as the present wire from the cutout to the ammeter. I have done this on my '32 but there is room behind the dash to work with. Remember that the gauge will read low.

Charlie Stephens

[Mike V. Florida]

Originally Posted by Standing Elk

What are your opinions on doing a 6 to 12 volt conversion. Thanks

Leave it alone and use the money you save on gas and drive it.

[jrelliott]

If you have a generator, you can hand crank it or push start when the battery is low. You cannot do this with an alternator. BTW if you want can use a stock generator and run a 12V negative ground system. Just change the bulbs, polarity of the coil, a 12V coil or a ballast resistor, repolarize the generator, swap the wires on the amp meter and a 12V battery. You can probably get a 12V regulator from Fun Projects or Tom Wesenberg that will go in your generator.

[pgerhardt]

Originally Posted by jrelliott

If you have a generator, you can hand crank it or push start when the battery is low. You cannot do this with an alternator. BTW if you want can use a stock generator and run a 12V negative ground system. Just change the bulbs, polarity of the coil, a 12V coil or a ballast resistor, repolarize the generator, swap the wires on the amp meter and a 12V battery. You can probably get a 12V regulator from Fun Projects or Tom Wesenberg that will go in your generator.

This is the first time I have heard this. Are you saying that when the battery is so dead it won't allow the coil to create a spark, a generator will supply enough juice at hand cranking speed, while an alternator won't?

[Dollar Bill]

Originally Posted by pgerhardt

This is the first time I have heard this. Are you saying that when the battery is so dead it won't allow the coil to create a spark, a generator will supply enough juice at hand cranking speed, while an alternator won't?

Have pull started many old cars and tractors with a dead battery.

An alternator needs to see battery voltage in order to produce current.

Also, a real-quick way to smoke test an alternator is to remove the battery cable while the engine is running.