Re: Evinrude 9.5 Pin Drive Props- 4 blade or high pitch available?
I hate to keep saying you contradict yourself but if you need half throttle to maintain control, lowering engine speed by chaning the prop worsens the control problem. Why -- for the simple reason you already require half throttle (that's half power) to maintain control. Increasing prop bite slows the engine down to be sure -- but it also means you need to pay much more attention to how much throttle you need to apply to maintain control. The key here, is if you can't maintain the speeds you want (0.5 to 2.5 MPH) with the existing prop, slowing the engine down and increasing pitch, blades, and bite will make that even more of a problem. The prop you are looking at, and others like it are typically used on pontoons because they need to push a very heavy load at very high throttle settings . Low pitch equates to power. High pitch equates to speed. Somewhere in between is a compromise for any boating situation I'm suggesting that doing what you want to do is not it for your situation. Here's another example. If you have an 8P prop now, switching to a 6P would pick up about 400 - 500 rpm and you would move at the same speed you did before, but at 3500 RPM instead of 3000. This gives the engine more power and hence more control than going the other way. Your car traveling down the highway at 70 MPH in overdrive (equates to a high pitch prop) has the engine running very slow. Step on the gas and you see very little change in performance which forces either a downshift or a torque converter release to get the revs up. Now drive in second gear at about 25 or 30 MPH and do the same thing. You will quickly see how sensitive throttle response and speed control is. That's low pitch, higher rpm vs high pitch, low rpm.
