[406 ss monte]

Anyone know how to hop up a gm alternator?
I have a 85 SS Monte Carlo with a stock 78 amp alternator on it, power every thing, & a after market ignition system. It just doesn't seem to be putting out enough power to keep the battery charged up very well. Headlights & heat at the same time is a big no-no. That pulls the charging needle almost into the red, but my other 85 SS Monte Carlo doesn't have this problem. The only thing i can figure is a weak alternator. What do you think? The electrical system of a car is my weak point. I was wondering if i could hop it up to a 100 amp myself, instead of buying a new alternator. Would this cure my problem?
thanks

[BodymanDave]

You can get a inductive amp guage you simply hold on the charge wire to check the alt. output for under $10.00 bucks. Check the output with no load versus load. You may have a bad alt. or perhaps a partial short or your heater blower is pulling too many amps.

[Restore60s]

That's a good idea Dave had. Also you can buy some of the Chevy heavy duty Alternators desgined for emergency vehicles that have massive electrical loads for about $68.00 at places like Advance Auto Parts.

[docvette]

[size=3]Doc here

The 100 amp and above alternators should be available for that car anyway as a stock replacement, I think they give options....60, 100..etc..So It should be a "Plug & Pray" operation.

If you have the stocker on there now, As everyone said, Check it's output and the electrical System for low output/high load conditions. Unless someone in the past under rated it to save a few bucks, It should support an otherwise good system quite well.

Try Autozone or other superstores, they have Load testers and usually will check for free!

Doc [/size]

[arch]

Yup, advanced should have 60/80/100/140/200? amp alternators for that car. They use to have the 200, not sure if they still do.