any recommendations on where i can buy a new alternator for a 73 dodge dart? also can i use a larger one and get away without rewiring the amp meter. The 40 amp alternator is pretty light as i want to add a moderately powered stero. Should i just run it off a second battery in the trunck with an isolator?

You've got various options in alternators, but in order to suggest one, it's necessary to know how much extra current you anticipate drawing.

So...how "moderately" powered, in watts or amps, is this stereo you evidently wish to play loudly enough for the rest of the world to hear whether they like it or not?

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

i was looking at a sony 4X 52 watt sytem. I was thinking of trying to use a remote control and not install it in the dash which still has the original AM radio. No major bass boxes but enough to hear it over what is not a quite car on the highway.

OK, so let's round up and figure 260w, which is 20 amps.

Other existing loads: Headlamps, stock type, with all other exterior lighting, maximum about 230 watts, so about 18 amps.

Ignition system, about 5 amps or so.

Heater blower motor, maybe another 8 amps.

Windshield wiper motor, maybe another 8 amps.

A/C compressor clutch, if so equipped, maybe 6 amps.

Let's add another 10 amps worth of miscellaneous loads (horn, dash lights, etc.) and we're now up to 75 amps, but you're not too likely to be running the high beams, the heater at max, the A/C compressor clutch, wiper motor, stereo and horn all at the same time. An alternator of 60A capacity would likely get the job done OK, while an 80A unit would do the job amply. Anything much beyond that would just be extra capacity.

Now: How much fabrication/modification do you want to do? An 80A alternator can be had in the same size/shape you have now, for direct bolt-on installation. They're not too difficult or expensive to get. But, if you're willing to do a little bracket modification/fabrication, you can use a Nippondenso 40/90A alternator from an '89-up Chrysler product (pretty much any Chrysler product) as long as it has the V-belt pulley used on '89 M-body cars (Diplomat, Gran Fury, New Yorker Fifth Avenue) and '89-'91 Dodge rear-drive trucks and vans with V6s and V8s. This alternator is a direct electrical drop-in, and the bracketry mods aren't terribly difficult. It is a smaller and lighter-weight alternator with an excellent reliability and performance track record, and has much better output at low RPMs than the older-type alternator you've got now. The main thing would be to get a quality unit; the "remanufactured" ones you get at the parts store are generally trash.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

THanks for the info. THe Nippondenso 40/90A sounds good but would I blow out the amp meter if i use such a powerful unit. I do have factory air and as it is now when i stop the lights get dim,the blower slows and the radio fades out. THere is not much electric power.

You would need to install a diode shunt to protect your ammeter, yes.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.