Need Cat advice

Sounds like Tasmania !

 

I grew up on the East coast, Long Island Sound, and Great South Bay, they had their days too. You had be able to read the clouds, and the tides, and every one on the boat hated you, when they saw nice sunny sky, and you said " it's time to go in" because the weather is turning bad. Not a way to be popular, but I always kept them safe.

 

It might be best to try it out rather than theorising.

As suggested above just do enough to get it running to see how you like it. No point in doing a lot of work which might be unnecessary or counterproductive.

Also how will you move it when the engine is not operating?

 

I converted this 20' Tornado cat with a heavy four stroke Honda. It's important to keep the weight centralized so I mounted it forward of the crossbeam. If your outboard has a round leg it will ventilate horribly without a transom in front of it. You can either build a fairing in front of the motor as I did here or put this fairing on the leg of the motor: Side Mounted Outboard Motors https://outboardfoil.blogspot.com/

 

The OP's boat is much smaller in displacement, 4 hp sounds about right to me. I remember a lunatic that put a 25hp two-stroke on a Hobie Cat, he took it on long run to an offshore reef, but I think only once, the report was it hobby-horsed like crazy, and was wet as all get out. Slow speeds should be OK.

 

Sorry for not responding yet, kind of crazy here. Wanted to wish my friends Down Under, A VERY MERRY CHRISTMAS!! You lucky dogs, you got summer there! Gus

 

Gary, nice power Cat, that is the idea I had in my mind! Sorry for not responding yet, kind of crazy here. Wanted to wish my friends Down Under, A VERY MERRY CHRISTMAS!! You lucky dogs, you got summer there! Gus

 

Thanks GUS, those sentiments are returned, but summer is looking a little too hot at the minute.

 

Mr Efficiency, I live in what they call the "High Desert". I've been here 20 years, my little ranch sits above the Arkansas river, and I'm 199' above the river, and 1/2 mile as the crows fly, from it. I have recorded 119.5*F a few times, and many winter nights, at -12*F, I have also seen 80*F change in 24 hrs. Monday night, I had wind gusts over 55 Miles an hour all night long. Tuesday morning I had to go out in the field and bring back all the concrete blocks, that flew away over night. lol,,, Gus