Re: 1994 jhonson 9.9 to 15 hp??
Nope. The 9.9 carb doesn't have the throat area the 15 carb does. Before spending your beer money on a carb, just look at the engine set up on the boat. You can improve performance here with some adjustments and maybe a prop.
Look at the anti-cav plate...that's the plate right over the prop. Make sure it's set at least even with the keel of the boat and better yet, an inch above. This takes a lot of the drag out of the water.
What prop are you running.....9 1/2 X 10? If so, change it out for a 9 1/4 X 8. This will get the rpms up. You would be very surprised what these changes will do for performance.
