Simply, the 10SI alternators have different rotor/stator combinations for different output amps. AFIK, the regulator and diode sets are the same. I used to just swap the rotor/stator to the 100 amp models and be done.
The unit I have had on my '72 here for some 15 years is a 17SI, it is factory rated at 108 amps, and is maybe a inch larger diameter with same mounting as another of the SI series....it's off a '79 Seville with Rwindow defogger.....one of my typical junkyard finds.....I dunno about the internal regulators being any different at all, they MAY be....
I know there are 10 and 12 in the series, but other than being smaller diameter than mine, I have no idea about the variations in amp ratings, or even if they can do better/worse than mine....
I look at it that my larger diameter unit certainly has better air flow for cooling, more room inside, and mounted in the typical C4 location above the headers, it needs as much airflow as can be gotten....
one of the problems with the newer CS series was inadequate cooling, they did have higher output at idle, but that tighter coupling and smaller diameter meant inferior cooling....problems....
supposedly solved by the CS144 series....I dunno, never owned one....
In spite of all the 'arguement' over 'there' through the years, MY 17SI works, so I leave well enough alone, besides I have a lifetime warrenty from years ago through AZone......
:chinese: