Re: looking for info on free wooden boat plans??
I have played with a few.......
Based on your smaller motor I would suggest an 8' boat (mini max) and the plans are here
http://www.muskokaseaflea.ca/staticweb/
The mini max is the smallest and normally has a 10 hp (9.9).
My only reservation is this.......an antique motor that is not specifically a racing motor should not be placed on a racing hull. You could shorten what's left of it's life and I have a soft spot for the older motors. If I were you I would build a smaller wooden skiff for that motor or hunt down a 12' aluminum hull.
Now...... hydroplanes are a blast! There is nothing like a wooden boat doing 70 mph and flying about a few inches out of the water. I still have another older home built hull in my yard that I will restore but that is on my someday list (someday I will get around to it). The one I have now is someday (there is that word again) going to get a 25 hp motor.
and here
http://forums.iboats.com/showthread.php?t=568781&page=2 post #28 is an earlier hydroplane I restored.
While I enjoy the speed I can no longer kneel down to drive them and maintaining motors that take all that WOT use can be pricey.
Take a look on you tube for the mini max
Have fun and good luck.