Alternator Options

Be careful of some of the Mopar ones. I bought a new 120 A (recall) one for an LA/BB Mopar that is supposed to bolt right up, because a good price on ebay (~$50). I didn't even try because it turned out to be much bigger and heavier than I thought from the photo. Might have been used in tow trucks & such. It has a front external fan, like a GM alternator. If anybody around Sacramento or Bay Area wants to try it, I'll sell cheap. I don't want to ship the beast. If I need more output than a squareback someday, I'll try a small modern Denso type like my minivans use.

TBI EFI has worked fine in my 65 big-block for years with just the stock round-back. I suspect it is only when you install an electric radiator fan that you need more juice. Don't calculate just based on the current ratings, since that is usually a high motor starting current (to size wires and relays). The steady running current is often much less. As long as your battery stays charged, you are fine. I occasionally put a charger on mine to see how long it takes to say "charged", to judge if the alternator has been keeping up.