was wondering if anyone had a suggestion on which pump to purchase I have a kubota svl-75-2 low flow only 17.5gpm I believe the picture attached is the the one I need
Direct drive or coupled to gearbox?
If you go to surpluscenter's tech page, they have all the formulas to calculate how many rpms it will put out, at a given flow and pressure. It has to do with displacement of the pump, in question. If you are marrying it to a standard 540 rpm gearbox, I'd shoot for about 700 rpm, to compensate for any wear in your pump...
Lets see the pictures of the brush cutter you built.
I'm going to run it with the gear box, I'll get some pictures as soon as it's done