commented in another thread (Aluminum slalom boat maybe soon) about a lighter smaller aluminum V6 for improved power to weight ratio. I have also pondered the same thing almost since the day I owned my first tournament boat (1987 Centurion tru trac II).
Why has one of the larger outboard makers not approached a ski boat manufacturer with a direct drive version?
These high tech aluminum block engines are lighter, more compact and have a higher wide open throttle or max. rpm range. Possibly being able to push speeds into the 50 mph range. Important if you also like to barefoot.
Yamaha makes a high tech 350 HP 5.3 liter DOHC 60 degree V8 (W.O.T. 6,000 rpm) that would likely be a little more compact than a regular low tech by comparison cast iron block push rod 90 degree V8 (W.O.T. 5,200 rpm). If you don't need as much power or you have a lighter aluminum hull Mercury makes a supercharged inline 6 with 300 HP (W.O.T. 6,400 rpm). Although I would suspect that the torque would not be there as it doesn't have the displacement at 2.6 liters. Bet that would skinny up the motor box.http://www.yamahaoutboards.com/outboards/V8-5_3L/specificationshttp://www.mercurymarine.com/engines/outboards/verado/pro-fourstroke/?model=1