Good idea. You could drive the air compressor off the front crank pulley.
Two big crank-connected cylinders pumping flat out will provide _much_ more air than anything you could hook to the front crank pulley. Though a York AC compressor makes a nice air compressor for smaller needs. The expense of some tinkering and a couple of reed valves is also quite low, when compared to other approaches. So it really depends on what you need versus what you can afford versus your available time for tinkering.
The 617 that I have with #1 rod broken and a semi large hole in the block runs as smooth at any of the other 617s that I've heard. Makes me believe that MB engines are so well designed that they'll run short a cyl or two....
Knock out another one or two and I think you'll find it's not quite so happy! 4/5 is a much bigger fraction than 2/4. The 4-cylinder Ford that drives a friend's generator was only running on three holes when he demonstrated it to me. It sounded a bit un-smooth to me, so I leaned over and plugged back in the fourth spark plug wire. I was familiar with the sound, because initially my 6-cylinder Hercules was also running on one dead hole, courtesy of a bad plug wire. Both of these were perfectly acceptable, but just didn't sound like they should. (And of course would have been substandard in the power department if stressed.) The Falcon I learned to drive in was described by my dad as gutless, and I heartily agreed. It was some weeks before we figured out that it in fact was only running on 4 of the 6 holes, due to bad plug wires. After that it seemed a _whole_ lot better! -- Jim
