Re: Help me reach my max speed
Over the years, I have strived for max speed from small outboards, including a '77 35hp Johnson. In the long run, including my current 18hp and 40hp Nissans, I prop for acceleration and control. They ended up being more important than squezzing the last mph out of it.
With small boats, people and gear make up a larger percentage of the total weight. The variability impacts reaching the required wot rpm range. Hence, many people recommend propping to your max load. If you prop toward a medium or light load, it will struggle to get boat on plane with heavier loads.
As suggested above, you can raise your motor on the transom to gain some mph. Most of the time, including your 35, you can only get about an inch, before the clamps are at the very top of the transom edge. A jack plate can get it higher but would be a waste on a boat like yours. If you do raise it some, after you test the high speed/straight performance and water/cavitation, make sure you also test the difference in turning radius at speed. I have had good straight-line performance, but cavitation on tight turns. If you have raised in more than 1/2" and are happy with all aspects of its performance, recommend adding the the trough transom mounting bolts, and not relying on the clamps alone.
FWIW, the '77 35hp Johnson on our 14' Alum Starcraft would hit about 28 mph with two adults and gear.
