Let me tell you guys what I am up to here. I was trying to see if I could run a Fecon Mulcher using my tractor for clearing my fence lines and some over-grown fields. The tractor comes with 16 gpm at the remotes, but that is not enough. I need at least 50 hydraulic HP to run the machine. 65 would be ideal. I can get a 63 HP gear pump, but it must turn at 2400 RPM, so I will have to add a shaft and gears. I just thought that if there was a 540 RPM PTO pump capable of this output, I would be in good shape.
As for the tractor's capability. I understand that hydraulic pumps are ~80% efficient My JD5420 is stock rated at 65 PTO HP. Add a turbo and turn-up the fuel, I can probably get it to 80 HP at the PTO (essentially make my 5420 into a 5520). That should get me in the ballpark. Forward and reverse locomotion will be at ~0.5 MPH or less. With these mulchers, the peak pressure and flow are not required at all times. So I will not be on the ragged edge all of the time. I am just trying to see if it is feasible.