SPF Minimum Amp Requirement

[Rob_R]

A quick question to the SPF owners out there. I currently have an SPF on order. I am sorting out my motor pulley options on the 392 stroker sitting in my basement. My question is does your assembly manual specify a minimum amperage requirement if all electrical items (lights, wipers, heater, cooling fans) are turned on?

Thanks in advance for any insight.

Robert

[Campy]

There should be no significant difference in amperage requirements between any Cobra kit car. I am using a 65 amp Ford alternator. I have dual electric cooling fans, an interior heater, and standard Cobra lighting. I have no problems running all these components and I maintain a sufficient charge. If you're concerned about it, you can buy a 100 amp unit for a little extra. If SPF will accommodate it, I would seriously consider a "one-wire" GM unit. They are all self contained and reduce unsightly engine compartment wiring. Summit Racing sells them in chrome as well as powder coated in a variety of colors.
Good Luck.
Campy

[DAVID GAGNARD]

Robert;

I think Campy is correct with the needed amps and also going to a one wire alternator is a good idea,but you can do it with a plain jane Ford alternator for 40 bucks.....Go to your nearest alternator shop and ask the owner to look thru his catalogs for the little gizmo that goes on the back of the ford alternator,it is a small voltage regulator that screws on the back of your alternator and turns it into a one wire alternator.....I have done it on three so far and all work fine.The part was 40 bucks and takes about two minutes to install....Wish I had the part number for you,but it has been a couple of years since I did one...The guy at the shop thought I was crazy when I asked for the part,but he found it in a parts book and was amazed,did not even know they made such an animal, now he converts them all the time......

David

[Rob_R]

Thanks for the answers, guys. Looks like 60 or so amps will do the trick. If I go with a plain jane Ford alternator, I will pursue the bolt on regulator.

Thanks again,
Robert

[Hal Copple]

On my 43,000 + mile SPF, with a Windsor stroker, i run the 60 amp ford unit, three wire, it has worked fine. I am aware of several folks that have had trouble getting a one wire to work, plus, an one wire has to have a certain mininim rpm to switch to charge. Something i don't fully understand, actually. I have found that alternators last 7-15k miles, before the engine compartment heat kills the rectifier in them. I just take the alternator off, have my local alternator shop put in a new one for $35 and put it back on. Less than an hour all told. Cheap. Once had a wire vibrate the nut off the back, went to full charge, and damaged my voltage regulator, put on a new one on a trip at a NAPA parking lot for about $20 or so. This is a two minute replacement.

The 60 amp powers everything i run, with no problems.

You are gonna have fun with your car.

hal

[DAVID GAGNARD]

Hal Is correct about the minimum rpms to "start" or "excite" the the converted ford alternator,I forgot to mention that.....With my stock pulley set up,it takes engine rpm of 1200 to "start" the alternator,once it is "started" it will operate at any engine rpm....when you turn off your ignition and kill the motor,it also kills the alternator,when you restart your engine,you will have to restart your alternator again.....Not a problem for me as 1200 rpms comes quick in first gear.....I have had mine in the car for three years now and 11,000 miles with no trouble so far......

It eliminates an external voltage regulator and a lot of wires and cleans up your engine compartment nicely....

David

[gsharapa]

I have a 1 wire 100 amp chrome alternator on my 514 SPF.

[khall]

Robert,
I have been having a bit of a problem with alternators in my new SPF (#1231). I initially tried a Bosch remanufactured 55 amp alt. with the SPF supplied regulator. The first alt. lasted only a few minutes, the second about the same. After a number of conversations with Mark at Dynamic, I tried a Ford Racing internally regulated alt. which is operating fine after 100 miles. It was a bit of work to rewire the harness, bypassing the stock regulator, but it works. I recently talked to another SPF owner who had the same experience (currently on his third alt) so it is not unique to my unit. I spent a considerable amount of time tracing wiring, bypassing the regulator, etc., and could find no obvious fault to account for the fried alts. No other problems with the SPF - very well built, and the customer service at Dynamic is great. But it does bother me that we were not able to find the fault. I would suggest that you start with the least expensive alt. you can find to test the system before you jump to the more expensive units. The Ford Racing unit is $150.

[Rob_R]

Thanks for the input, folks. Does anyone know where I could get a wiring diagram for hooking up a 1 wire alternator on a SPF?

Thanks,
Robert

[DAVID GAGNARD]

Rob;

The one big hot wire coming out the back of the one wire alternator goes to the battery side of the starter selonoid.....On my Mustang it is mounted on the passenger side inner fender.....That's all there is to it,that is why the one wire alternator is so simple........

David

[Jack21]

I used a plain vanilla Delco 63 amp 2 wire unit (12SI). Delcos' in my experience have been drive 'em for 100,000 miles, replace the brushes, and drive 'em for another 100,000 miles.

The BAT terminal goes to the battery, and the Ign terminal goes to the ignition to energize the windings. There is a short wire on the side plug that goes to the batt terminal. Runs electric fan, heater, wipers, halogen lights, MSD box; plenty of juice, and no reliability issues whatsoever.

Have heard a lot of grief about SPF alternators. Don't know why, but the ordinary Delco might be an option.

Also used new Powermaster Starter instead of OEM Ford. 1/3 the size & weight, twice the torque, and 4x the service life. Cheap at $159.95. Summit.