K-85 63 amp alternator option

[Chevy Dave]

Why was this offered on AC equipped cars with the standard 61 amp alternator? A 2 amp increase was not much, was the 63 amp more durable?  Did it offer a higher output at idle? It appears that the 63 amp one has a case similar to the later 10SI interregnal regulator models. If anyone has any info on this subject I would appreciate it.

Thanks,

Chevy Dave

 

[Canuck]

I wasn’t even aware there were two different alternators. 

[Chevy Dave]

I have done some research on the subject, including speaking with Mark at Mad Electric. The 63 amp alternator puts out more amps at idle and at lower rpms. I have verified this testing with my 63 amp alternator and a 61 amp off of another car. You can directly replace the 37-61 amp one with the 63. The 63. amp looks like a 73 and later 10 SI, but does not have the integral regulator or the diode trio.