Would it be possible to reroute the drain oil from the left front cylinder stud to the transmission case above 4th/5th gears?  That way you wouldn't need a pump and gravity would do the work.

I don't know if that would provide sufficient oil flow to be of any benefit.

Armen, I don’t have any pics of the filter cut open.  I should do that on my next filter change.  I’ve been meaning to make a test rig to see what pressure the bypass relief lifts.

Dave, that’s pretty close to what I’ve been planning.  Take the oil off the valve spring pockets and dump it on 5th gear.  That way nothing gets robbed from any of the pressure fed components.  Left front stud hole serves as the drain for the exhaust spring pocket.  The intake spring pocket simply spills over into the cam chain cavity.  I’m planning to plug the stock drain port for the exhaust pocket (left front) and drill a new drain laterally.  Make a lateral drain for the intake spring pocket (left side).  Then connect the two drains and run the drain oil through a small cooler with magnets inside.  Then direct that oil over the top of 5th gear.  I don’t think I can place the flow directly into the mesh.  Most likely it will have to dump on the top of the output gear.

Versy, that’s an interesting suggestion on the relief valve.  If I increased pump capacity (tandem geroters) and installed a pressure relief valve, I could plumb the escape piping to discharge on to the overdrive gears.  Mighty complicated job but I bet it would be fun.  Quite a juggling act to get the filter bypass relief and a pump discharge relief to work as intended and end up with a filter that isn’t continuously on bypass.  Another good reason to build that test rig and see where the filter bypass lifts.

Sorry Armen, I don’t have those photos right now.  I will try to post later.  I can tell you that it’s a typical gerotor pump and both the outer and inner rotors are easily removed.  I’m fairly confident that I could make an extension for the housing and stack another rotor set.  That would essentially double the capacity.  The ideal option would be to grind the additional rotor set to about one-half the original thickness.  That should increase capacity to 150%.  I don’t have access to a surface grinder.  I don’t think I could do it with a tool bit.  

Then, could install a relief valve in the plugged hole in the engine case.  All this would depend on the filter bypass set point.  The filter bypass set point has to be significantly higher than the relief valve setting.  Actually, doesn’t need to be a relief.  Could be a fixed orifice.  Just adjust the size of the orifice to set the flow so that my current oil pressure could be maintained.  If the new oil pressure (as measured at the head cover) remains close to my current pressure, then all the additional flow should be goin to my gears.

Good point on cavitation.  I assume by “feed side” you mean suction side.  The suction foot and screen look like they could be easily modified, but the casting with the suction channel might be difficult.  It’s clearly an engineered shape with a gradually decreasing cross section.  The pumpage is very hot and there’s zero suction head, it’s always lifting the pumpage.

It would also be wise to enlarge the discharge channel in the right side engine case, not sure about the discharge & suction ports for the geroter, they look like they are timed.  Not sure, I don’t know much about gerotor pumps.  Time to light off google.