were chrysler square back "78 AMP" alternator true 78amp or just marketed that way by chrysler ?

[rustytoolss]

Question were the 1981-1987 Chrysler square back alternator really 78 AMP...or just marketed that way ??? I ask because most every parts store lists them as 60 AMP . I have read that the 78 AMP units had a very thin stator ring. Any input would be great. Thanks

 

[Don67Satellite]

Some 3rd party parts stores often do not list the correct tech specs for things. When shopping for alternators, I saw some places advertise an alternator I knew was 95 amp from the manufacturers website, but 3rd party places had them at 85, 70, and 60 for the same unit. I use manufacturer specs over some lazy website creator.

 

[Kern Dog]

I've read that the amp rating is also misleading since almost all rebuilt alternators have the small pulley.....which increases the charge rate anyway.

 

[Nacho-RT74]

Yes, they are 78-80 amps. I have the output chart somewhere of one rebuilt by Beck-Arnley. When I find the file, will post.

 

[4406bbl]

Question were the 1981-1987 Chrysler square back alternator really 78 AMP...or just marketed that way ??? I ask because most every parts store lists them as 60 AMP . I have read that the 78 AMP units had a very thin stator ring. Any input would be great. Thanks

Yes they were 78 amp at like 2500 rpm not at idle, that is why the police cars and optional alternators were 100 amp at 900 rpm leece-neville alternators. The stator was not thinner, just had a raised set of lamination in the middle and a different case set that made it look thin compared to earlier stuff. They work better but are nothing compared to a leece or modern denso unit. Alternators also have a duty cycle, factory stuff is 30% leece-neville is 100%. Check out leece-neville idle pro alternators on the web, upgrade your wiring if you use one, even the old 100 amp had 4 ga output and ground from the factory, and bigger field wires.

 

[Nacho-RT74]

True, they max ouput was around 2000-2500 rpms BUT getting increased the max output also gives more output at iddle ( around 50-60% of its max output) which is tipically the max output given by the older alts, and pretty much enough AND BETTER for the basic stock car operations giving enough juice to keep the batt out of the game 80-90% of the regular running time, preventing from heavy discharge status at amm.

Those alts are a bit thicker than the older units, maybe couple of milimeters, so in some cases trimmimg the rear alt spacer and using longer belts ( just and inch or two ) will make them fit better. BTDT

Some of them got large pulley, so changing to the smaller pulley available will get you more juice at same engine speed, increasing alt speed.

 

[Nacho-RT74]

I couldn't find the pic on my PC but since I have uploaded several times, it can be found already uploaded at some other Mopar boards