electrical system design.

[Stuart]

I was just sittin' around thinking about what electrical devices that I will be running in the t-bird and if my battery will hold out for each 1/4 mile run. I won't be running an alternator.

He's what I'll have:

Moroso electric water pump drive kit
Duraspark-II ignition with an MSD-6AL or crane hi-6 box
Holley Blue electric fuel pump
5" Sunpro Tach
Ford probe electric cooling fan - (to aid in cooling if needed)

I've got 2 batteries here, one is small and lightweight the other is a 700cca and heavy. I plan on installing a very simple electrical system - I'll be doing it myself. Anyone got and tips or idea's for me?

[Site Admin]

All sounds good !

Here is my tip..................Get a minimum 15 amp charger and a generator and put it on after each and every run.

[sam]

My tip is to get a small alternator off of a GEO or a SUZUKI (3 cyl.) one wire self exciting regulator and mount it and run it off the engine, the horse power you will lose (about 1 hp) as opposed to the aggravation of trying to keep the battery charged between rounds and in the case that you progress on in rounds this could cost you a round in the manner of not enough power to run your ignition system properly and fuel system.

[Stuart]

SS10, I was batting that type of idea around but I'd prefer not to have any accessory drive system if possible. What are you guys running for batteries and do you have any issues if you go deep in to the elimination round?

[sam]

Stuart I run a 10si gm alternator that I built up and it puts out 43 amps at an idle and 110 amps at 1800 rpm. It also has a self exciting regulator. I drive my truck on the street as well as race it and believe me you do not want a sortage of power for those ignition systems and fuel pumps, found that out the hard way.
SAM

[Site Admin]

With good and decent size batteries that you keep charged while in the pits you will have no problem even in the final rounds but consider this:

If your main reason to eliminate the alternator is HP and weight, the savings may be a lot less than you think.

The lower voltage that you will have with no alternator could result in HP loss depending on your ignition source, cylinder head and compression configuration.

Removing a 10 lb alternator and bracket will gain you approx. 1/100th of a second on the E.T. - Big Deal Eh?

It is a myth that an alternator uses 10-15 or even 20 HP.

There are 746 watts to a horsepower so it becomes
obvious that even a 100 amp alternator is only going to use a couple of HP and then only at full output.

Another myth:
Installing an underdrive pully on the alternator will save HP.
Wrong again. Here is why.

What many people fail to comprehend with the alternator is that if you slow it down, the voltage regulator will simply crank up the field excitation
to whatever value it takes to maintain voltage. The mechanical effect is the torque requirement rises as the speed decreases IAW torque*RPM/5252 = hp. Since watts are the same as hp, the alternator will
draw a constant hp to supply a given watt load. The only difference will be the very minor air drag difference.

Wana make HP ? Get rid of the belt driven water pump. You will gain as much as 12 - 20 HP depending on the pump. Be advised the electric pump theafter used will cost you HP if it does not cool the engine properly. Remember +Heat= - HP therefore + E.T.= Frustration cause the car slowed down.

[Stuart]

I've got the electric water pump drive kit now so that's going on for sure. I wasn't thinking of any big HP gains without the alternator, I saw a Car-Craft article that dyno'd engines with and without alternators, the average loss was 1HP. I was mainly looking to simplify things but maybe I'll just go with a small alternator. ;D

[Site Admin]

;D ;D Good thinking ;D ;D

[sam]

;D ;DThat is the best way to go, one of those alternators that I mentioned, weight one and you will be surprized at how little they weight . You can fab all brackets out of aluminum because it is a strip car only, don't have all the vibration of street driving were steel is easier to use, unless you have a freind with a tig. ;D ;D

[Stuart]

I can weld with a TIG, we have one at work if I needed to make or fix something. I'll see what I can find for a alternator over the next littlw while.

[Scott]

I may have a stock 5.0 altenator, but it may require more wiring then you want.

[Stuart]

Is it internally regulated? and whats the price?...I get most of my stuff used from a friends salvage yard for free. ;D ;D ;D...He supplied the car, engine and some used parts and in return his company name goes on the side of my car - a good deal for both sides if you aske me. ...I have to remove it myself as part of the deal. If he does wan't anything for parts it usually requires payment in either 6, 8 12 or 24 pack quantities....LOL...I always ask him if he wants anything for the used stuff or else it would feel like I'm stealing from him, he treats me great so I try to return the favor when I can. ...I was thinking I might go down there on Saturday and look for a couple of parts I need for the race car project.

[Scott]

Find me a altenator pully off a 2.3 mustang and the strator wire off a 130amp mustang altenator ;D

[Stuart]

what for? The best part is that my buddy is a Chevy guy, he say's the Ford stuff is worthless to him....Maybe thats why I like him so much. ;D ;D ;D...it's not worthless to me. I think he just gets a kick out of watching me poke around for certain parts...I'll look high and low until I find them. He finds it funny when I find something that I get all excited about... ...I found a 9" truck axle to narrow and use under my 63, he gave it to me for a 24....sweet deal.

[Scott]

im adding a 130amp altenator to my stang and the stock pullie is too large so it wont charge good enough. i have underdrives on my current alt so they wont work. So i guess a 2.3 pullie is smaller. the strator wire is just that, a plug and wire that goes to the 130amp alt. i can just use a female spade connector, but i thought if i could find the actual strator wire id use it. but no worries