FAQ - Kitty Hawk 26
1) Can I power the KH26 with twin 150's?
Yes! I have now modified the plans to allow for twin 4 cylinder outboards, up to 150 hp each. The KH26 was designed around a single Honda BF225 outboard with a weight of around 620 pounds. The 4 cylinder Yamaha F150 weighs about 491 pounds. That gives a weight of 982 pounds. This weight will put the stern of the boat down about 1 3/8" deeper in the water. The bow will come up about 2 1/8". This isn't too bad and should work fine as long as you take care to not load the back of the boat down with other heavy loads, like a 50 gallon baitwell or your giant brother-in-law. Twin V6 outboards are too heavy and cause too much trim disturbance. I do not recommend them for this boat!
2) Can I install an outboard bracket?
Yes! I have now modified the plans to allow for a single engine up to 300 hp and 640 lbs. on a bracket. Twin engines on a bracket are too heavy and will cause too much trim disturbance. A bracket will move the weight of the outboard aft about 30". When you calculate the trim disturbance of a weight, it is actually a moment measured from the Center of Buoyancy of the hull. If the outboard weighs 620 pounds, then we have an additional moment of 1550 ft/lbs. On the KH26 this will sink the stern down by about 5/8" and the bow will come up about 1". Not too bad and should work fine. Twin F150's will put the stern down by almost 2 1/2" and bring the bow up almost 3 3/4". That is way too much trim disturbance and could lead to poor handling and poor low speed planing performance. Lets not even discuss twin V6 outboards on a bracket!
3) How about a straight inboard? I have an old 6-71 Detroit laying around in the back of my shop.
The KH26 was originally designed for a straight inboard. The engine was under the console with a straight shaft. The issue was underwater hardware, namely the strut. I looked everywhere and just couldn't find a stock strut that would fit. My attempts to find someone who would cast one for us were also frustrating. As I am not comfortable with welded up stainless struts, we then switched to sterndrive power. That led to the current outboard design which really simplified things. I still have the preliminary inboard drawings, but with outboards being so reliable and efficient these days, I think the reasoning behind using an inboard on this size boat is getting a lot less sound. Outboards are easier to build, faster, more efficient, quieter and smoother running. As for that old Detroit, please send it to be melted down into something more modern and useful!
4) How about an express version with a cabin up forward?
The bow of a Carolina style boat is a very small space. With a flush deck and just a raised portion aft, there really won't be much room up there to do anything. If you want an express, I think you should be looking for something in the low 30 foot range, maybe with a 10'-11' beam. No, I don't have anything like that hanging out in my files!