Hey Neil, yes it’s up on the Acme page on Bookface. I would say a good snappy PS Thirty would out work a Rd4 or the “new” thirty. That is if the load in question fell into the ps thirty’s gear range. Hook up a harrow or set of drills that the newer tractor could pull in forth and it would be a different story.
I’ve had my PS Thirty hooked to a four bottom plow and I was impressed by how it handled it. It’s a fresh engine so I would expect it to run good. I’d say the PS thirty might be more comfortable to run as well. Steering clutches pull about the same. And the PS has a nice wide seat. You get plenty of heat off the manifolds with the PS that you don’t with the RD4 or 6G. There were a few PS Thirty’s around our part of the world, but like all of the gas burners, fuel consumption got them parked in favor of the diesels. From what my grandpa and uncles tell, there was one PS thirty on our ridge. Everyone else still used horses. Once the diesels came out, Cat or IH, tractors appeared almost immediately. There were six RD4s on our ridge alone, along with an Rd6 and RD7. Another neighbor had Td35s and Td40s.
Plows, PS thirty was usually teamed with 3/14's here in the heavy rice soils, Sixty or D-7 pulled 5/14s I was always told the larger the share, the harder they pulled. Seldom does one see moldboard plow in use now, many are gone, few as yardart or in the bone yards