posted 01-27-2004 03:35 PM ET (US)
We have a 20' aluminum all-welded hardtop boat in which we putt around Puget Sound and the west side of Vancouver Island. We've run both an 8-hp Honda and a 15-hp Evinrude for kickers, both 4-stroke. The extra 7 horsepower is good for all of maybe 0.5 mph (~5.5-6.5 mph tops for both). On the Honda, I'm not aware of any available aftermarket low-pitch "sailboat" prop. We bought one for the Evinrude, and it's more responsive (particularly in reverse) than the factory evinrude prop or the honda.
The hot kicker ticket right now is the Yamaha and the Merc with the bigfoot lower unit--look for a funny-looking elephant eared prop with an unusually large hub. In reverse, exhaust turns 180 degrees in the hub and runs out the front of the prop, and therefore your blades bite clean water for good response backing into a slight current or wind while jigging.
We nearly get this bigfoot effect with the sailboat prop on the evinrude, but the real deal is more positive.
Shaft length: 20-inches should be right. Verify that anti=ventilation plate is about level (+/- 2") with hull at installation spot.
Power--I don't think that you can use more than 8-10 horsepower for a boat that size. I see many larger boats running the 9.9 Yamaha. I'd be eyeballing the 8-hp Yamaha with the big prop.
-JV