Van's numbers are a good place to start.
The rule of thumb is that power required is proportional to the cube of speed and the quoted numbers more or less agree.
For climb, an extra horse power should give an extra 33,000lb.ft/min of lifting power. E.g. at 1800lb weight that would be 18.3 extra ft/min of climb. But that assumes the propeller turns torque to propulsive power with 100% efficiency.
That's likely to be nearer 70-80% thrust efficiency, so say 14 ft/min per extra HP. Van's numbers give 250ft/min for each 20HP increment 160-180-200 so broadly in agreement.
p.s. I see you are in Menlo Park. I work in MP and live nearby, so would be happy to help if you're short of a bucking partner any time (I suffer from RV building withdrawal symptoms).