When you start narrowing or shortening the inside sponson, you will start to affect the boat's abillity to support itself on its right side. When you enter a turn, there is a greater chance of "nosing under" because the sponson drops lower in the water. I agree with Jerry, the boat runs great the way it was designed. I watched Bruce Mooring run away from the feild at the Outboard Championships here in the Pacific Northwest last year with his D 27. But if you feel the need to reinvent the wheel, then I would tend to agree with Lohring on this one, make the inside sponson just a little bit deeper than the outside one......Good Luck