6v Generator vs 12v alternator

[Sniper]

Trim to fit, 95-2000 Ford Contour fan.

 

 

[James_Douglas]

I have been running a 6 volt POS ground alternator for 15 or more years. I have a six volt electric pusher fan that I use now and then.

 

I have never had a problem with it in 15 years and about 70K miles. I strongly recommend an alternator if you are using an Optima Battery. See my posts from 17 years ago or so to read up on that.

 

James

[chrysler1941]

Electric fan is a nice option to complete the modern car illusion in a classic car. Sounds like a hoover when engine is turned off ?

[Plymouthy Adams]

Hoovers suck if I am not mistaken....?

 

I can see this on a modified car or one with questionable exchange air or water at the radiator and as a preventive measure on towing or long hauls on a steep grade.  T hey have their uses and advantages....

 

My British van build incorporates a super slim electric fan as a pusher as the larger engine install really has not much room for the standard engine driven fan.  Of course this is not stock, would never want it stock...as I could not be happy at 62 MPH at mega-revs

Edited October 30, 2021 by Plymouthy Adams

[Sniper]

1 hour ago, chrysler1941 said:

Electric fan is a nice option to complete the modern car illusion in a classic car. Sounds like a hoover when engine is turned off ?

Only if you wire it to run with the engine off. 

 

 

[Los_Control]

Ok I will throw in my worthless 2 cents. 

Parasitic draw is real. You can eliminate it if you are building a race car with no cooling or charging system.

 

I would say 12 volt probably would be least parasitic draw for a few reasons.

1, electric fan. You could possibly just leave it off while driving, Just turn it on at long traffic lights when needed. Less parasitic draw then a mechanical fan

2, LED lights. (I hate them) they take less juice to run, means less time the alternator is charging.

3, More options for amps on a alternator ... get a 100 amp alt, will charge your battery lickity  split, less parasitic draw.

4, I would venture to say, a modern alt would have better smoother bearings then a 70 year old jenny with a worn shaft ... Less parasitic draw.

 

IMHO the op is not really interested in trying to stay & look original if willing to install a electric fan ... I'm cool with that, think I am going 12 volt also.

I think between 6 or 12 volt, a real scientific study would show 12 volt winning parasitic draw.

 

I just find it interesting the electrical question was written around parasitic draw.

Makes me wonder if the op is more interested in building a Hot Rod racer then a stock classic. I'm fine with that.

Choosing the correct transmission & rear end can remove a lot of parasitic draw. Much more then the electrical system.

[OUTFXD]

I plan on keeping the car rather original looking  on the outside.  I do plan on upgrading to  LEDs but want ones that look like original lights,  Not interested in "Angel Eyes" or projector  lights.  I am not terribly concerned with keeping the engine compartment 100% original looking (Though I have put thought to having the 6v generator rewound to 12v neg ground).  I am interested in decreasing the Parasitic load of on the motor as a means to increase Efficiency, Performance and lessen Emissions.

 

I have considered upgrading to a overdrive transmition,  though that would be a project Whaaaaaaaaay down the line.

 

And yes, I know a flathead motor is not a good starting platform for an efficiency build.  but I just love how smooth they run!  so I guess you could say I am just taking what I have and making it better.

Edited October 30, 2021 by OUTFXD

[maok]

You will get better and worth while efficiency from a quality tune up, bump in compression, and even a pertronix module in the distributor.

[OUTFXD]

Tune up was a given, Petronix is already in the plan.  Had thought about milling the head to bump up compression but that needs further investigation. all great suggestions though!

Edited October 30, 2021 by OUTFXD

[Los_Control]

Trying to think of a proper example for mechanical parasitic draw.

Lets imagine a 727 transmission and a 8.3/4 dodge rear end connected to a flathead 6 engine ... not even sure if it is possible to install the 727.

The result of the heavy transmission & rear end would almost make the car undriveable.  Just all the weight of transferring the horsepower from the crank to the wheels.

 

Now if you installed a lightweight T-5 transmission and a light Mopar 7.25 rear end, there would be less parasitic loss.

 

Same time the factory overdrive transmission will present more parasitic loss then any electrical problems.

 

I think what you are concerned with is torque.  People with the overdrive love the performance of the flathead 0-60 mph & driving down the freeway.

Not a Hot Rod but gets the job done.

And it would not bother these cars if they were 6 or 12 volt. Simply would not be a noticeable difference in performance.

[OUTFXD]

insofar as Transmition/rear end, I am mainly  concerned with lowering RPMs at cruise on the freeway. I didnt know the factory overdrive was such a dog!

 

Another topic.  Petronix vs 70s Mopar Electronic Ignition.  I read an article about swapping our stock innards into a slant six Distributor.  Seems like that would be a great way to put Tried and true Electronic Ignition into the car.  However it would be WAAAAAAAY more complicated than swapping in a petronix Mag trigger kit.  Thoughts?

[Plymouthy Adams]

not to mention the Mopar you can walk into a store and walk out with repair parts if needed...I can really see the coin toss needed here....(being snarky...lol)  to me those wishing to stray from stock points, I see no need to leave Mopar...

Edited October 30, 2021 by Plymouthy Adams

[Young Ed]

1 hour ago, OUTFXD said:

Petronix vs 70s Mopar Electronic Ignition.  I read an article about swapping our stock innards into a slant six Distributor.  Seems like that would be a great way to put Tried and true Electronic Ignition into the car.  However it would be WAAAAAAAY more complicated than swapping in a petronix Mag trigger kit.  Thoughts?

It's not complicated at all. I used a long bolt chucked in a cordless drill as a redneck lathe to slightly reduce the OD of the /6 housing. Once you get it to fit in the block the rest is just basic dist reassembling and installation

[OUTFXD]

13 minutes ago, Young Ed said:

It's not complicated at all. I used a long bolt chucked in a cordless drill as a redneck lathe to slightly reduce the OD of the /6 housing. Once you get it to fit in the block the rest is just basic dist reassembling and installation

True true!  I was thinking more along the lines of wiring for  the old EI system.

[Sniper]

I have all the parts to do this swap.  But I am not going to use the Mopar control box.  Using a GM HEI module and a Ford coil.  Seems that's the hot combo these days.  Probably going to use the EFI to control the ignition, once I get the fueling sorted.