i bought the red powder coated one from summit. wasn't happy w/the powder coating, looked more like ceramic paint so i put the guts into my chrome casing one. had it for 5 yrs now no prroblems

 

OK, I'm getting even more confused now. As soon as I passed my E.E. courses in school, all that knowledged simultaneously leaped out of my brain.

I've just bought a new 100amp alternator which has one wire hookup, but I'll still use the old positive and negative posts. I'm also adding a dual Spal fan setup to the mix and will wire off of the alternator. I was planning on running an 8 ga. charge wire from the starter to the alternator to beef up the main source a bit.

Does that all sound good and will my ammeter work? Relay unit for the fans will be a custom unit with 2 50amp relays.

 

My understanding is that the ammeter only measures current flowing from the alternator to the battery, or current flowing out of the battery when alternator current is insufficient. (exception - the ammeter never shows starter motor cranking current.)

In other words: if the battery is completely charged up, and the car's electrical loads are consuming 100 amps and the alternator is producing 100 amps, then ammeter will read "0" amps. (because no current is going into the fully charged battery.)

If you wire your electrical fans to the alternator output, the fan current will not effect the ammeter reading if the alternator is producing enough current. Actually the alternator output typically goes to a horn relay terminal. This terminal serves as the main current distribution point for all electrical loads (except the starter). Air Con/heater, lights, radio, are all powered from this terminal. This is really the terminal that the fans should be connected too also.

My opinions expressed above applies to my understanding about early C3's. Maybe the later ones were wired differently.

 

You can connect anthing you want directly to the alternator output. If you don't put a fuse in line with your load as close to the alternator as possible then your asking for trouble.

 

Be careful.......Today's Fuel Injected ECM's and similar ignition electonics don't like a noisey power source. As a matter of fact most recommend connecting close to the battery taking advantage of it's low source impeadance / clean power. Seems like we had this discussion not to long ago

The result of that thread pointed to this as a excellent information source
http://www.madelectrical.com/electri...evymain2.shtml

The third method discribed is the best solution in my opinion.

Bullshark

 

Nice looking Daytona

I have the Chrome Power master from summit. 106 amps. I replaced most of the small guage wiring with 12 gauge over the years just so I don't have brown outs or melt downs

I have one Spal fan come on with the ignition key and the other i installed a 50 amp toggle switch off of the fuse panel so I can run the fan even if I'm out of the car or if I need extra cooling both of them are running.

 

Lets see if I can remember my course 'BS101'...

True, there is less electrical noise at the battery terminal. This is because the battery acts like a big capacitor, making it a low pass filter; any noise at the alternator or induced on the cable are basically absorbed by the battery.

However, the battery doesn't actually supply power. The alternator puts out ~14V when the car is running. Current flows into the battery (charges it) because 14V is higher than 12V. No current will flow from the battery unless the alternator is putting out less voltage than the battery. The battery is really only needed for starting the engine. A side benefit is it filters noise.

If you are running loads that don't care about noise (motors) then it doesn't matter if you connect at the alternator. Any decent automotive electronic circuitry would have its own voltage regulation circuitry to compensate for noisy power, I wouldn't be afraid to connect at the alternator.

As for the link I agree with switching to larger cables. The only down sides of too big cables are cost and extra weight. It is nice to have a separate terminal block to connect all your loads to like they have. They need to incorporate fuses into thier diagrams. Fuses save lives people (and time & money as well).

Theoritically I like the idea of connecting the remote sense line at the distribution point. Practically it won't do much for you unless you have a voltage drop across the alternator cable, which means the cable is under sized and should be upgraded anyway.

Sorry Scudd that this is not about your original topic.

 

Boofers.

Yes, However, only if the noise isn't to big.....such to induce large back emf voltage spikes and take out your internal alt regulator (or other aftermarket electronics). Good low impeadance wiring ( no old loose splices) and good grounds should help protect against this. However, I think it might be a stretch to classify the older C3's as "Any decent automotive electronic circuitry" Just wasn't designed for today's sophisticated electronics.....but might be good enough if you feel lucky I just don't want to take chances with my $500+ RamJet MEFI ECM when those dual Spal fan inductive motors kickin on and off That low impeadance battery (capacitor) can help this if its close. The regulation response of that old internal regulator with high rise time voltage spikes is the question for me.......a new regulator is cheap in comparison ($15) Good power distribution and solid distributed grounds like that indicated in the hyperlink can save alot of problems later.

They did......they used fusable links. old technology but still effective.


Bullshark

 

And that happens how often?

There are no fuses in thier diagrams between the alternator and the fan relays, horn relay or headlight relays.

 

Every time the fans cycle power off! They are large inductors!! poor grounds make it worse.


My dual Spal fans have fuses built into the provided wire harness, .... The 14 gauge fusable link feeding the power distribution terminal strip in the hyperlink schematic is acting as a fuse for the headlights. Be carefull fusing the headlights....you don't want a momentary short (such as a headlamp burning out) shuting down all the headlight at night.


Geezz Boofers.....don't take this dialog as adversarial....just trying to provide a little guidance......take it for what it worth

 

So you blow your internal regulator every time the fans cycle power off?

I'm not taking it as being adversarial... I'm just waiting for you to recognize my superiority complex.

 

Boofers……..What’s that old saying…..Arguing with an engineer is a lot like mud wrestling a pig………all you get is tired and muddy before you realize the pig likes it!

Bullshark

 

Bullshark I knew you would come around to my way of thinking

 

noob here... I was just wondering why you would want/need a higher amp alternator?

 

You add devices that weren't considered at the time drawing more amperage than the stock system can put out. Electric fans and high out put stereos, etc and the next thing you know you have a battery drain with the stock alternator going full out.

 

I'm replacing my radiator and adding electric fans. The fans draw around 30 amps. I only have a 66 amp alt, so that wont cut it . I need a larger one.

 

They sell 130 AMPs and 200 AMPs. I bought one for my 5.0 Mustang GT.
Just like the CHP Mustangs Special Service Package.
Makes a difference all right.

 

Additional accessories, like electric fans, stereo amps, electric water & fuel pumps place too big of a load on the stock 63? amp alternator.

So I put one of these...


...between my alternator and horn relay. I attach all of my high draw accessories here, like the dual electric fans. I have a 100amp Powermaster and it works great so far.