My boat is 16'11 with a 9.9 Suzuki and a 90HP Mercury. I fish restricted lakes with just the electric or the 9.9 all the time and the cold Merc just steering, I did try a 20hp computer on my last boat with a similar 9.9 engine it didn't plane with the extra HP so I swapped props for a month and I got like 2mph for my $1000 so I'd never do that again. I got a ticket once I was 6 miles from the launch and it appeared to be a tornado blowing down the lake. I fired up the 90HP and hauled away from the incoming doom, then continued on to the launch but the warden was down there too where it was pretty clear. Nice guy actually I admitted guilt he went easy on me. There's no law in NY against having a motor that's not used. Hull speed is like 7 or 8mph that's all I got on the restricted waters.