Replacement of a Generator with an Alternator

A previous owner installed a rebuilt '71 engine in my '73 SB. Everything I have read indicates that this engine is equipped with a generator, yet ours has an alternator.

Is there a good reason why someone would have replaced the generator with an alternator? Does it improve the electrical system somehow? I wouldn't think such a switch would be very easy (though electrical is not my forte).

The reason for the conversion is to increase the amperage output; generator = 30 amps, alternator = 55 amps. If you're going to use fog lights plus a killer stereo, you'll need the extra juice!

We don't have fog lights or a killer stereo, but I guess the extra amps can't hurt.

An alternator is able to put out higher amounts of AMPS at lower RPM.... a generator has to speed up to create more/same amount of amps. Alternator is better IMHO....

An alternator has a lot of advantages over a generator. The main one is that it eliminates the voltage regulator 20plus bucks and I have replaced a few because the generator had gone bad....by the time I replaced every thing I had spent twice as much as I would've if I had bought an alternator. They are just a lot easier to hook up and cleans the engine compartment.

You may have noticed my question on the Newsgroup about replacing a generator with an alternator -- someone wrote to say that people do that to get more power (30 amps vs 55 amps) to run fog lights or big stereos, etc. We have neither; I don't know the history of the car well enough to know what motivated the PO to install an alternator--I guess it's okay.

We have an interesting combination -- definitely a '71 block, but from what you say a later fan shroud, and it has an alternator rather than a generator. Quite a hodgepodge.

Certainly no harm in having a bigger unit than needed - the regulator only allows as much as the electrical system needs. I think the '73s came with the alternator as they added the booster fan in than year. The generator has only about 120 watts spare with all the lights etc on, and when you add about 100 watts for the fan (I'm guessing, but this is what most car fans run at), your battery charge current would be minimal with the boost fan running, and just a generator. The alternator has plenty of reserve.

Retro-fitting an alternator is very common - the only other modification needed is the regulator, and this wiring depends on whether the alternator has an internal or external regulator. Either one is easy to alter, and both give you 600 watts in lieu of the 360 watts of the generator.

We have a 1971 engine, which I believe was originally equipped with a generator, which is smaller in diameter (at the back end) than an alternator. I don't know why someone would have made that switch, as (I think I recall you saying) it requires some fairly serious rewiring.

It's actually a very easy change to make to the engine -- it would need the later fan shroud for the alternator, as the alternator is a different length and needs a different mounting plate where it meets the shroud; a new shorter oil filler stand, and that's about it.

I imagine the reason it was done on your car is that it originally had an alternator (original '73 engine), so does not have the underseat regulator like mine (it's built into your alternator), therefore fitting the appropriate alternator to the '71 engine is easier than rewiring the car with a regulator and using the '71 generator. Also gives you more amps of course, and this is useful because you have more electrical gear than the earlier bugs (fresh air fan for example).