In 2001 there was a record breaker underway, the RECORD by Fabio Buzzi:

http://us.wannahaves.com/item/babefa...cord-powerboat

A friend of mine came along with a broken Graupner Azimut Challenger and told me, to do a new model from it. So I showed him the Record and he decided to make the model.
I lenghtened the hull of the Azimut with balsa wood made a new surface with much filler, sanding many hours.
The deck got sidewalls and the superstructure was build from balsa and ABS-plastic too.
Next thing was the powerunit.
After removing the Graupner tunnels for waterjets, the hull was closed and two shafts with Speed 800 motors went in. The esc can handle about 100A in one direction only and batteries are 16 green Sanyo CR. Props are counterrunning 37,5mm diameter.
Each rudder got a servo with metal gear and now, after some years running the model, I changed the radio to 2,4GHz. The antenna is lenghtened a little bit (from originally 30mm at the receiver to 300mm with a extern antenna on the deck). I have no probs with this arrangement and the model is running fine.
My "Record" gets a speed of about 40 km/h and looks very realistic for it's size. Scale is 1/20.
The pics are from our last meeting in august 2009.

Here are some more pics...

Looks good FATBEECH! Wonder how fast you could get it to go with a brushless system in it. Might be more of a scall record breaker!

Looks fantastic FB! That is quite a big job you did.

MarcRacer, you do not need brushless to go fast.

Nice work!

I like all the decaling, and that guy casually hanging on the stern rail in a full speed turn.