Well, I'm not Rick, but I am another casual observer . . .
The previous poster who has the exact experience you were asking for, tells you . . .
No matter how you do it, an ice hull adds weight so calculate that into your engine HP, prop and gear reduction so you don't end up under powered.
You seem to conveniently over-look what that means. NOTE AND UNDERSTAND the man telling you
this is currently running a 427 with a blower AND a 2.55 ratio gearbox AND is turning an 82" 5 blade prop ! !
Your response was "I've been looking at Rotax and at some older jet ski engines".
Your first post read like you were somewhat knowledgeable about this subject matter. Your second post reads like that isn't the case.
A five foot wide airboat with an engine like you've been looking for would be perfect for "just getting rid of cabin fever during the winter."
, as long as you were intending to do that in the pasture behind the house. However, if "The purpose of the boat is specifically for ice fishing on bad ice"
, you would likely save a lot of money and stay a lot warmer by just sticking with the jon boat.
When Pato said what he did above, the implication was to first build the hull as it needs to be and THEN
get enough power to enable you to operate it safe and effectively. This implication seems to have completely eluded you.
You simply can not start with with an under-powered engine and then shrink the boat to match the lack of power.
The Laws of Physics aren't variable and don't much give a damn about a man's good intent or budget.
I suggest you do exactly as Pato suggested and call/talk to Diamond Back and/or Hammat about building you an ice hull and what power they recommend. I would bet that you would find that enlightening.
Nothing wrong with asking questions, but you may be better served to first figure out the [SEARCH]
function and do some reading as there is already a lot here about building an ice capable hull and their characteristics.