Hello ,new to the group and the Y block. Recently bought a 64 f-100 with a 292 . I'm wanting to change the gen for a alternator set up, what is every ones recommendations ?  

I just did my 56 using the old style gen1 Alternator which uses the external Regulator. Others will suggest the One Wire General Motors type because they are easy to hook up. They don't charge well at Idle Speed. You can use the existing Generator Bracket using threaded Rod and Spacers. Do a search on the Internet. I used that on mine. I will post a Picture.

  

One wire is the way to go, unless perhaps you have loads of aftermarket accessories.  My truck has an electric fuel pump and aftermarket ignition which probably draws more the the stock points, in addition to the stock equipment and with that I've had no charging problems.  If you have fuel injection, electric fans, or a high powered stereo that might change.  I haven't had a chance to find out.

Since the alternator will not be made for the application, you may need a pulley with a different diameter than is equipped with the alternator for the best results.  You want the alternator to be turning at no less than 1800rpm at idle.  With the most common Y-Block damper, that will require about a 2.20" pulley for a more or less stock engine with a stock idle speed.  For a performance oriented engine, the pulley must be large enough to keep alternator RPM below 18000rpm at max engine RPM so it can become a balancing act.


Lawrenceville, GA

Correct me if I'm wrong but don't the self exciting alternators charge at idle? It's been a while and I'd have to check again to confirm this but I think the one I put in my 56 does.

Durham Missouri

Yes, they charge at idle.


Lawrenceville, GA

It’s a matter of what you like and experience. I’ve seen too many 1 wire installations that don’t provide the proper charge voltage at the battery. At the alternator terminal, yes. And some that won’t start charging revved up. I always connect the gen light hookup to excite the unit. This is particularly true of the GM units.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

It is usually easier to get a "three wire" GM style alternator - and a simple "jumper" modification will rig it for use with the idiot light. In factory installations the third wire is a "sensor" lead that detects voltage present over in the wiring harness and adjusts the alternator regulator to boost voltage to suit. On a "one wire" installation with a heavy gauge lead to the battery, there is not much (if any) voltage drop between the alternator and the battery and the system works well. I have a chunk of #6 welding cable on mine - virtually  zero drop. Trouble can develop if you use too small a cable to the battery and the "sensor" is not reading the same as over at the battery connection. Digital volt meter will catch this. 

 
 Steve Metzger       Tucson, Arizona

Steve explained that a lot better than I did. My problem is I’m usually trying to fix a problem on someone else’s car, and running a new #6 cable is not in my work description.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

get the Motorcraft (Ford) 3G.. 
http://www.oldengine.org/unfaq/3ag/3ag.htm

wreaking yard they run around $20 - 30... 

Reman  around $70  + -  

New   $$$

pull one from a  3.8 V6   need to get a V pulley for it if you don't have one
and you might need to put a spacer behind it...

I did this swap on my 351c years ago, and just now doing it on my 
56 Packard... 
  I used the pulley of the 2g, but had to make a spacer, to  get the pulley off
the Alt body  I got a washer with a 5\8 hole, then ground it down to fit the 
recess that the pulley fits down into. You will not be able to use the normal 
lock washer. Also the upper mounting bolt I think is metric so if you get one
from the junk yard, take both bolts... you can figure out the rest
 OH and get one with 180 deg  opposed ears, they come in 3 configurations.
Best

Thanks for the info guys . I ended up buying a napa 2133041 alternator but now I'm not sure how to wire it up , Help !