chris wrote:
have a 5 hp merc would a lesser pitch give more torqe on an Aquarius 23?


Not exactly. The amount of torque developed by the engine
isn't going to change. What will happen is that the lesser
pitched prop will move water more slowly, although more of it.

The real question is, will it drive the boat better? To
answer that you should have a good idea of how fast the boat
is moving at the engine's peak RPM. Does the engine fail to
get up near redline, with the boat scooting along and making
a large stern wave? If yes, then less pitch is exactly what
you need. Or if the prop stream is a lot of froth & bubbles
and the boat is not really being driven (this is less likely
IMHO).

If the engine is getting up near it's top end, and the boat
isn't going as fast as you'd like, what you need is a bigger
diameter prop (and possibly less pitch) which may or may not
fit on your Merc drive leg.

Hope this helps

Fresh Breezes- Doug King