Volt meter vs. amp meter & 1 wire alternators

[DAVID GAGNARD]

Originally Posted by mjhcobra

Ron Francis said no way on the amp meter-my assumption is that the rest of the harness makers agree due to the gauge not being able to register more than a 50 amp charge. Seems stupid unless I use a 50 amp alternator, which again will not work. Final decision - 100 to 125 amp alternator with volt meter.

Still trying to decide on the single wire vs external regulator - any pros or cons????????

my 2 cars are both 65 Mustangs,street car and a race car, I use a volt gauge on both with the "old style" Ford alternator converted to a one-wire unit......Simple $40.00 conversion, takes about 1 minute and you only have one wire from the alternator to the battery side of the starter seloniod,clean and simple....the way I like it, simple is always better for me....

Personal prefrence is a volt gauge, accurately tells you what your alternator is doing or not doing...I don't worry about the amps, just make sure your alternator is not overloaded amp wise.....I would add up all the amp useage your car could pull at any given time and use an alternator that can supply that + 40%........if your total amp useage would be 40 amps you should have a 56 amp alternator, a standard 60 amp Ford unit would be sufficent......

I run a standard 60 amp old style Ford unit on both car and never have had any problems......idle speed, volt meter shows 12 volts, 1,000 to 1,500 rpms or more, volt meter shows between 13 and 14 volts...

David

[mjhcobra]

Thanks David for the insight. I saw on a previous post where somebody added up all the power that are drawn on an alternator. I will use it as a guide if I can find it. I guess originality is second to safety on this issue.

[DAVID GAGNARD]

Originally Posted by mjhcobra

Thanks David for the insight. I saw on a previous post where somebody added up all the power that are drawn on an alternator. I will use it as a guide if I can find it. I guess originality is second to safety on this issue.

I would suggest you add up the max amp draw of each electrical device on your car, that'll give you the most accurate amp useage for your car........then go from there.....

Either the "old style" voltage regualtor or the one wire unit both work well and do the intended job, it's more of a personal preference to me which to use....

Which ever way you go, check out this site, a lot of useful info on amps/volts/wires/wiring..........

http://www.powermastermotorsports.com/charge_wires.html

I adhere to the KISS principle, cause, I smart enough to be fairly good at few things and dumb enough to be dangerous at a LOT of things!!!!!!!!!!!!!!!!

David

[Blas]

Trans brake = 12 - 20 amps
throttle stop = 5 - 15 amps
fans = 6 - 25 amps
cdi ignition = 3 - 36 amps
hei ignition = 6 - 10 amps
nitrous solenoid (each) = 5 - 15 amps
electric fuel pump = 3 - 12 amps
electric water pump = 3 - 12 amps
instrument panel = 2 - 4 amps
brake lights = 3 - 6 amps
running lights = 3 - 10 amps
an MSD 6 or 7 series ignition consumes approximately 1 amp/ per thousand rpm.

[mjhcobra]

Thanks, that's the list I was looking for.

My car has the following:

2 front fans @ 4 amps = 8 amps
1 fan behind radiator = 20 amps
Instrument panel = 4 amps
Brake lights = 5 amps
Headlights = 10 amps
Holley Red fuel pump = 10 amps
Wiper motor = 10 amps

Assuming that I am stuck in traffic, its raining with wipers on, at night with lights on, and all fans are running-I would be maxed out at 67 amps at an idle. Add 40% more to ensure you have 67 amps at a loaded idle and you get 94 amps.

Does this sound accurate?

I want to use the original alternator and regulator rather than a single wire alternator. Sounds like 95 to 100 amp alternator should cover me with these loads. Anything I should look for in my search for the correct alternator and regulator?

Thanks for the guidance, Martin

[DAVID GAGNARD]

Does this sound accurate?

I want to use the original alternator and regulator rather than a single wire alternator. Sounds like 95 to 100 amp alternator should cover me with these loads. Anything I should look for in my search for the correct alternator and regulator?

Thanks for the guidance, Martin

Sounds accuarate to me.....I'd go with a 100a unit for your application.....I'd give Powermaster a call, they show old style/new style and chrome units in 60a/80a/100a/140a/200a........they could also give you some info on the voltage regulator and wiring.......

David

[mjhcobra]

It is interesting that there have been no comments on the part the battery plays in this issue. I got a pm from another member who brought up the point that the battery is like a box of amps and that the alternator keeps it charged.
What about the thousands of British cars that have heaters, fans, fog lights, wipers, etc and they all run with a 4 cylinder motor and a 45 amp alternator and an AMMETER.
Additionally, the big ford cars of the 60's and 70's came with 55 amp alternators and they had all kinds of power options and AC-some had ammeters, some had volt gauges, some had idiot lights. Just some thoughts on the subject.
I will still probably go with a volt gauge for the safety aspect, but still am not clear about the high amp alternator that is being suggested.