For Those Who've Swapped RV2 For Sanden Compressors...

Actually all those compressors are reciprocating type. The difference is in the "firing" order. The Chrysler is a 2 cyl V configuration. Think like a Harrly/Davidson engine (uneven firing order) The York/Tecumseh is a 2 cyl with a even firing order. (every 180 degrees) the Sanden, and Chrysler C-171, and the Ford FS-6 have 6 cyls, with a even firing order every 60 degrees. So a much smoother load on the drive system. The Total amount of power to drive any of these compressors does not vary much. It is how the load is spaced on the drive system.
PS: That is why the RV-2 compressor has a much larger clutch and pulley. To smooth out the uneven pulse loads.