My mag recently went out on my T and I haven't had much time to figure that problem out yet (just ground the valves, rebuilt the carb and gen), so as a temporary fix, I stuck a 12V battery in the car. I did a lot of research on this forum and have driven another T with a 12V battery in it and know of the problems that 12V can have with the bendix in the starter. I was wondering if there was any way to add some sort of a resister or something to lessen the impact on the starter. I dropped the battery in, hit the starter and BAM! Those 12V hit the starter HARD and the engine fired up immediately...scared me half to death after I've gotten used to 6V. I now see what people mean about 12V being hard on the starter, but it runs so much better now that I hate to switch back to 6V, at least until I get the mag fixed. Too many projects, too little time...

Put a 4 gauge 12 volt cable from the starter button to the starter.The longer the better, cuts down on some of the impact.

Brett,
I have used a 12V battery for over 8 yrs. and have not had any starter problems so far. I also find the engine starts immediately using 12V. The starter may fail the next time I start the car....However, that can happen using a 6V battery also. My starter, bendix and spring are original ford. I question the quality of "After Market" bendix parts/spring. Suggest you find another good complete starter as a back up.....as I have done. That way....hopefully, you will never have any starter problems and can watch dust collect on your back-up. Smile! Les

Brett,

I disagree that long cables or small cables will save the bendix and ring gear from all that impact when operating on 12 volts. Until the starter finds the flywheel and picks up the load, the current is low so also will be the voltage drop in those resistive cables.

A better solution in my opinion is to use a 6 volt battery for the starter and a 12 volt motorcycle battery for the ignition.

I know there are many folks like Les that use 12 volts to the starter without problems but why take that chance when 6 volts is unquestionably easier on the starter drive and flywheel ring gear?

Seth

I agree with Seth, i have a coupe so two batteries in the trunk is not a problem, six volt to the starter and twelve for everything else, just have to charge the six volt every week or so when touring.
Rick

Rick,

Just have to charge which 6 volt battery? Your generator (or alternator) doesn't charge the series two (12 volts)? Lighting is 12 volts?

My apologies for all the questions!

TIA, Seth

OOPS!

Now I see what you are doing. I guess I could have read your post better.

My apologies again!

Seth

Seth, i use a six volt for the starter only, i use twelve on the ignition and lights and back-up camera and Pertronix ignition, i have a alternator for the twelve volt and need to charge the six volt every few days or as needed, i haven't figured out how to charge both while driving so no more than i usually start the thing the six volt battery will last two weeks while touring.I use a starter solenoid and a key switch, i had a large bullet hole in the dash in just the right spot for a switch.The way its wired you can't start the car without both batteries being turned on,you can hand crank it with the twele volt on. Rick
Rick

This is how a friend of mine in New York is doing it. Two 6V Group 1 batteries. Becker alternator with 12V regulator charging both batteries (in series) simultaneously. Car's electrical system is 12 volt except for horn and starter which both operate off the grounded (lower) battery.

Seth

I thought I remembered a post a while back where you said you used a 6V bat for the starter and 12V for the ignition, which I thought about doing too. I don't have much room in the trunk (barely enough for the gas tank!), but I was thinking of rigging up a two place battery carrier to mount both batteries under the car. Then I could use the generator to charge the 12V and just keep the 6V battery topped off with a charger. Once the car's warm, I usually crank start it anyway. Hate to add any extra weight to the car, but I also hate to tear up my starter!

I have used 12 volt for over 20 years. I never had a problem. I collected plenty of starters over the years as spares, so I am not concerned. I think the 12 volt v/s 6 volt argument falls into line with the "coils v/s distributor" or "original v/s restored" "engine painted v/s no paint" arguments.

Brett,

My car only had one battery so it wasn't my car. Mounting a second battery underneath the car might be difficult unless you have no exhaust system under there.

If you do charge a 12 volt battery with that generator, it needs to be a full-sized 12 volt battery unless your generator also has a Fun Projects regulator.

If you need lighting for nighttime driving and have an "electric car" combo switch, then the lighting and the ignition is going to be at the same voltage unless you remove the little bar that connects the battery+ from the outside contacts to the inside ones. I know this is getting confusing!

Since I really don't know what electrical components you have on your speedster and what your driving habits are (electrical needs are), I really can't recommend a strategy so that you can have 12v for your coils.

If you'd like to discuss it further but not here, sethharbuck@bellsouth.net will work.

Regards,

Seth