al and judy-
There are many thread topics that deal with this topic in one way or another under
Outboards and Sysems.
Here are the basics:
The original Classic CD-22 (c. 1980) was designed for a 70 hp 2-cycle outboard of about 250 lbs.
The CD-22 Cruiser, first produced in 1987, was certified for 90 hp max.
The max hp was raised to 100 a few years later, about 2000.
This was raised to 115 hp a year or two ago.
Next set of basics:
70/75 hp will plane the boat, and is perfectly adequate for most normal loads at sea level to a few thousand feet in elevation. Yields 26-28 mph usually.
90 or 100 hp will give you more margin for heavy loads and accomodating elevation changes. Yields 28-32 mph usually.
115 hp is usually not needed at all, but if you'll usually be operating at 5000 feet or more and with full loads, may be useful. If you opt for this, get a motor with electronic fuel injection because the computer automatically adjusts fuel/air mixtures for the elevation/conditions. Engines with carburetors need to have their jets replaced to provide a leaner mixture for the thinner air. When going back down to sea level, the jets have to be changed back or the then too lean mixture will cause overheated engine failure.
Insurance issues:
Here things get a little fuzzy, because of the different companies, procedures, and policies involved, but some generalizations are possible:
The insurance company may or may not know the maximum hp allowed by the engine manufacturer, but will ask how many the motor provides. You may send up a red flag with a larger engine, particularly if the insurance company knows it's beyond the rating. If so, plan on paying for it or even being denied coverage.
THE BIG CAVEAT here is usually stated thus:
What will happen if you 1) have a big injury/liability producing accident, 2) it's allegedly your fault, and 3) the injured party's lawyers find out you were driving a boat with a "hot rod" motor with more than the maximum hp rating???
How do you like your(own) dead meat roasted, Sir?
There's even another dimension to this, which is how maximum HP ratings are determined by the manufacturer and the suggested guidelines used by the Coat Guard. Check this out:
Maximum HP Ratings
Generally, this is not one of those topics that yelds simple, agreed upon answers. Others may want to add their own two cents or perspectives, but it is fairly easy to say that the C-Dorys in general
1) do not need a lot of hp to perform well
2) do not respond well to high end hp ratios (get squirley)
3] are definitely not Hot Rod type boats. If you want one, there are much better boats for this type of lifestyle.
(I saw a new world record of 258 mph in the quarter mile in the IHBA Nitro Nationals here at Red Bluff last June!)
Hope this begins to answer your questions!
Joe.
