[Bushwacker]

You're wise to be paying attention to weight. Remember these boats were designed in the late 60's when the heaviest outboards were the V-4 OMC's and the I-6 Mercs, weighing 300 lbs or less! They aren't designed for the weight of modern 4-strokes, so they won't perform or ride as well as designed if you hang nearly 500 lbs on the transom! (Check those 4-strokes weights carefully - they're usually dry weights, so don't include the weight of 5-7 qts of oil plus the gear oil, and they often don't include the weight of the cowling, so the actual wet weight is often closer to 500 lbs!)

On my boat, I had a significant CG shift when I repowered and went from a 300 lb V-4 on the transom to a 429 lb motor moounted 30" back on a bracket! It raised min planing speed from 12-13 mph to about 20 mph and it hurt the ride, and remember that the Seafari is less stern heavy than the cc's to begin with! I had to go to a stern lifting 4-blade prop and a Doelfin to get back to where I originally was.

Although most folks today seem to think that a 20' boat with less than 150-200 hp is underpowered, I believe that they're biased by experience with the relatively inefficient conventional deep-V hulls. The SeaCraft VDH hull has been proven to be at least 10% faster than any other deep V of comparable weight and HP, and they will easily plane at low speeds if properly balanced. Power selection should be a function of how you normally use the boat. If you run offshore in rough water a lot, you should know that the relatively light 20' hull will start to go airborne at about 20 kts in seas of about 3' or more. If you often run in thosse conditions, you won't need (or be able to use!) more than about 115 hp! In my own case, I ran a old 115 (about 90 hp at the prop) for over 30 years, mostly offshore including a 1/2 dozen trips to the Abaco's, and I always felt that I had adequate power. When I repowered, I initially considered the 115 E-Tec, but they were not in production at the time, so I went with the 150. In hindsight, I have subsequently found myself taking extended cruises with as much or more weight than I have ever carried in the past, so I'm glad I went with the 150, although it took me about 6 months of experimenting to get it to ride and handle right. Even with a heavy load, I can easily cruise at 25 kts at 3700-3800 rpm and over 4 mpg avg, vs. 20 kts at 4500 and 2.8 mpg with the old motor! Plus I can easily cruise at 30 kts at ~ 4100-4200 if I have to, which is about as fast as the old motor would run at WOT!

On the other hand, if you only run in flat water in the ICW, then fine, hang 200 hp on it and let 'er rip!