Trolling motor prop selection

Fishing yesterday, 3 Feb 17, my buddy was having a hard time contending with the wind - which was gusting from time to time. Seems his trolling motor, Minn Kota Max, was either a little too slow or too fast. He couldn't find a speed that would give us some forward thrust in the wind without speeding up too much. Is there a prop recommendation that would give a little more thrust, down low, with a little less top end? I would appreciate any advice, of his behalf, so we can catch more fish.

The boat is a Ranger RT 188 with Yamaha VF 115.

Sorry to say not much choice on changing out prop. Couple of company's sell after market props touted to give more power with less draw. But that is debatable. Best thing to solve your problem is a variable speed motor. I assume it's a 5 speed. Might call Jones trolling motor and talk to him. I talked to him about fixing a foot controlled 5 speed and there are parts to turn it into a variable.