That looks like a blast! I love fast outboards. Been messing around with them for years which led to a bunch of free work on a lot of my friend's boats. Guys shell out big money for hi perf bass boats but have no clue on props,setup,or basic maintenance.
You might try raising your motor up on the transom a little and going with less trim to level it out some. Be less susceptible to chine walk.
Hey Thermod - I've always had a boat in my life - love to go a little faster too.
I can get most things done on a motor myself, but far from expert.
There is a group on Face Book called Vintage Outboard Tunnel Hulls for more pics.
I'm also in Vintage Outboard Mercury Fanatics (on FB).
Do you post anything about boats anywhere?
By the way - would love to go up a little more with my motor, but need a nose cone for water pick up, and a bit more transom height.
I agree the trim is way too high - there was zero wind that day and I was trying the third hole up on my trim settings (need power trim) - would never run that much trim on a normal basis.
My prop is a 14 x 26 Ron Hill Cleaver, I'm running it about 1 inch up into the tunnel which is not enough for that prop.
The prop seems to be sucking the back of the boat down into the water at speed - I think this is because its being run too deep for a cleaver.
I think the rotating blade coming out of the water is pulling the back of the boat down rather than the blade entering the water providing stern lift.
I want to be high and flat at speed with this boat.
I would like to see more rooster tail from the engine rather than the sides of the boat (like whats happening to me in the video).
In the attached pic the flat board indicates the bottom of the sponsons, and the T square is flat on top of the board - you can see the propshaft is about even with the bottom of the sponsons.
In the video, I raised the motor up about 3/4 of an inch from this position. - don't have enough transom to go any higher.
Disregard the bronze prop - not used.