Thanks to all those that made suggestions about making the Suction Hoses, here are my efforts. The boat looks OK now thought there is much to do still. I am using two Johnson drill motors in paralell with one 50 amp ESC & 20A fuses in each motor + supply lead, all running on 8.4V NiMhi. the current props are 40 X 21 three blade. The boat is fast enough but battery life is short and the battery is very hot after the end of the run. I water cooled the motors and ESC. I will try some smaller props and 7,2V to see if there is an Improvement.
I like the design of your motor cooling, what tubing did you use to wrap around the motors?
Jon