Joe -
I'm talking outta my ear on this one, so take it with a grain of salt. Other 'Bolters with real experience can give you the correct info.
A low cut-in generator starts charging at a lower speed. More specifically, it starts producing a voltage equal to that of a fully charged battery. The armature is wound to produce current at low RPM's and a second winding to produce current at higher RPM's. The output amperage is lower in order to keep from having to increase the size of the armature and generator case by a large amount.
The voltage regulator is designed and adjusted to match the low cut-in generator.
I don't know if 1100018 and 1100028 are physically different on the outside. The '29-'57 MPC shows the overall length of both is 9-1/2 inches.
> '29-'57 MPCBy the way, Ken Warner "Kennethw" at ClassicGenerator built the generator that is on my truck. He wound it for 12v and matched a regulator to it. They work great and look new. The 12v regulator does not have the screws through the top of the cover. I replaced the blank VR cover with a Delco-Remy cover that I bought on Stovebolt.
- Lonnie