alternator idle amps

[sternwake]

Ideally, well depeleted house batteries would be fed high amperage until 14.7ish volts is reached at the battery terminals.
Getting back to 80% charged in a 30 minute drive is much better than getting back to 65% from 50%. Sub 80% charged, battery charging is fairly efficient, the trick is the voltage regulation seeking mid to high 14's at the battery terminals.

Also driving, not just parked and idling. RPM is important, underhood airfow is important. Heat kills alternators and when maxed out, they get hot, fast. So underszed widiring and lesser electrical pressure can also be considered an alternator life prolonging measure, but likely at the expense of the house batteries, depending on the usage.

I can swap out my alternator in 15 minutes, and its cost is not a bank breaker, but this is certainly not the case of every vehicle and vehicle owner out there.

The stereo guys simply want to prevent discharge and maintain 12.8+v at the battery terminals while powering those huge amplifiers.. As far as I know.

I don't think the amplifiers work better at 14+ volts compared to 12.5v, but could certainly be wrong. My sony 104 watt stereo head is good enough for me. Most of the acceptable sound quality, is the kenwood 6x9's on the doors.

[Optimistic Paranoid]

The stereo guys simply want to prevent discharge and maintain 12.8+v at the battery terminals while powering those huge amplifiers..  As far as I know.

I don't think the amplifiers work better at 14+ volts compared to 12.5v, but could certainly  be wrong.  My sony 104 watt stereo head  is good enough for me.  Most of the acceptable sound quality, is the kenwood 6x9's on the doors.

I'm sure you're right.  My point is that you can probably find brackets and idler pulleys through those sources IF you wanted to do a second alternator with it's own separate (hopefully adjustable) voltage regulator for your house batteries.

[Blacktank]

for gm all i could find for stock upper drivers side alt mount was for the 60's short water pump,there is aftermarket stuff,lower passagers mount but then you would be running both alts off the same belt
most were putting the alt to far out for a van engine bay


but this one would work


$80 something for it though

[Ballenxj]

I'm sure you're right.  My point is that you can probably find brackets and idler pulleys through those sources IF you wanted to do a second alternator with it's own separate (hopefully adjustable) voltage regulator for your house batteries.

Tis indeed a good reference point.

[MN C Van]

The PCM (read as Voltage Regulator) maintains the optimal output of the generator by
monitoring battery voltage and controlling it to a range of 13.5 - 14.7 volts based
on battery temperature

   


Change these values, you change output voltage.

I replaced the computer, and used a 70's external voltage regulator (no battery temp sensor as on modern cars). IIRC, it will do over 15 volts in extreme cold temps.

[MN C Van]

Yes, the 1976 Factory service manual says values for -20° F  Voltage range is 14.9 to 15.9

So, in short, on a modern vehicle, if you wish to manipulate 'generator' output voltage you change the battery temp sensor value.

On the old car ... hang an ice cube on the voltage regulator!

[RepublicOfTXPatriot]

Very Good Information ! Thank you !! I'm gathering components for my house and solar system. This info will be very very helpful !!