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I just wanted to correct a misconception: the RV2 isn't really a "power hog", it just seems that way. The amount of shaft power needed to drive a compressor depends on the compressor's displacement, volumetric efficiency, isentropic efficiency, mechanical efficiency, all else being equal. Certain other factors affect this as well, such as how much oil circulates in the system. Less oil circulation results in improved efficiency, and compressors with sumps like the RV2 circulate much less oil vs "modern"* axial piston compressors. Overall, from published results, twin-cylinder compressors like the RV2 and York are actually more efficient vs axial piston compressors like the Sanden, Seltec, Denso, GM a6, DA6, etc, and other swash and wobble plate compressors.
The reason the RV2 (and York, Tecumseh, RM R4) has the reputation as a "power hog" is twofold. First, they DO use a lot of power, but in return you get a very high refrigerating capacity due to their large displacement combined with high volumetric efficiency. Second, this large effective displacement combined with a relatively small, inefficient condenser results in higher head pressures, which increases power usage. Similar displacement "modern" compressors actually pump less refrigerant due to lower volumetric efficiency (VE), which means they have less capacity but also lower head pressures and thus lower power input requirements. Another thing that I think contributes to this is that the two cylinders have large torque fluctuations per revolution compared to axials with more cylinders, so when the clutch engages against head pressure the immediate response is more noticeable.
If you're not concerned with a totally accurate restoration you may want to consider safely packaging and storing your original tube and fin R-12 condenser and installing a modern (no quotes) parallel flow condenser. Sites like UAC have dimensions for OE and universal parallel flow condensers. You need to watch for the tubes and mounts to make sure a given condenser fits in the available space, and you will want to make adapter brackets to mount it without modifying/hacking your original core support. Within the constraints of your original condenser or available mounting area, you want the biggest, thickest parallel flow unit you can fit. This is true even if you use R-12, and especially true if you use R-134a. A parallel flow condenser will reduce head pressure and provide more subcooling, which will increase system capacity and efficiency while actually reducing power consumption by the compressor. A win-win-win.
All that said, you are otherwise correct: The RV2 is simple, reliable, easy to rebuild, and HEAVY! Who cares? You don't have to hand-carry it wherever you go, and it will outlast 10 Sanden compressors. Just run it for a minute or two every couple weeks to keep the front seal oiled, and it will stay refrigerant-tight and last an extremely long time.
* I put "modern" in quotes because the axial swash plate and wobble plate designs are not new. The first such design mass produced for automotive use was the GM A5, back in 1955. That makes the axial piston design just as old as the Chrysler V2 and York and Tecumseh twin-cylinder designs. GM replaced the A5 with the A6 in the 60's, with the A6 being another axial piston swash plate design. The only thing "modern" about the current Sanden, Seltec, Denso, etc. compressors is that they are light weight and disposable. You can replace shaft seals in them, and even valve plates, gaskets, and o-rings in some models, but once they are worn out you throw them away and get a new one. I guess this makes them just like the modern vehicles they are put in. You won't see 50+ year old versions of these "modern" compressors that just need a new seal and gaskets, because they will never last that long.
