Re: will reducing prop pitch always lower top end speed?
All sortsa different views. Well, here's another, just based on stuff I've read. If you keep the same diameter, then going to somewhat *lower* than stock pitch improves "hole shot" (initial acceleration), because it lets you rev faster (where your engine is more powerful) when you're moving slower. (Going *much* lower than stock pitch, though, overdoes it, and the prop basically just spins in the water.) If you go somewhat *higher* than stock pitch, you sacrifice even more in terms of low speed acceleration (which is why the stock prop wasn't that high pitch initially), but you go faster at WOT, since with the stock prop at WOT your engine isn't working its hardest. If you go *much* higher pitch than stock, then you reduce the RPM's the engine will go at WOT (again pulling it out of its sweet spot), and increasing the tendency to be more of a drink-mixer than a prop. To understand all this, it's helpful to imagine props with wacky pitches: almost none (you go nowhere, and the prop slices through the water putting no load on the engine), and almost 90 degrees (big load on engine churning the water, but again you go nowhere). So, not only is the ideal general purpose prop a balance, so are the ideal WOT prop and the ideal hole-shot prop.
