How much amperage can an alternator support? no really...

[Brett Dikeman]

On Feb 4, 2008, at 12:14 PM, Vittorio Bares wrote:

> I've got 580 watts of lights on the rally car, this will require  
> 48amps
> to run. Typically the 4000 has a 90amp alternator, I know I could go
> with the heftier 110amp alt from a 200 or what not.
>

The rated output is only at maximum speed and sometimes only for  
intermittent duty- as they heat up, output drops quickly.

If you google the part number or hunt around, you should be able to  
find a RPM vs. current chart.

Brett