As you can see by the thread dates, this idea has been around for several years. Since then there have been newer motors and overseas there are classes that have good boat counts and NEW SCHOOL RACERS.
THE BOAT has to be a tunnel design true tunnel or Mod VP
wood, or composite or combination of both
production made or home built
10 to 14 feet in length
No cells
The boat can be a kneel-down style with no trim and hand throttle
OR
foot throttle, seat and power trim
THE MOTOR
30 to 50 hp 2 stroke or 4 stroke
2 strokes have a max displacement of 45 cubic inches
4 stroke is horsepower rated only 50 hp maximum
Rules are same as T750 with one big difference...WATER PICK-UPS
What makes these small motor tunnels really perform is the sponson mounted water pick ups
Those along with a nose cone allow the gear case to be out of the water at speed with little drag on the gear case.
Better than a speedmaster!
You can see the two pick ups and tubes on the back of the F4 Tunnels
Some racers can get real performance out of a 30 hp
https://www.youtube.com/watch?v=IDg45ezSvZE