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[quote=Edchris177]I have found that the top speed , as shown on the screen of the device, is always 1-2 greater than what the device actually calculates. I do not know why this is so, but it happens.
If you hook the GPS up to your computer & extract the data, you see this, every time. 
I looked through a recent data log from the 5.0. GPS showed "max speed" as 20.5mph. It had logged 592 segments, that varied from 30 metres to several hundred metres. The highest one was 19.9mph, over 157 metres. I think that is fairly accurate, as one run remained at 19+ for nearly 6 kilometres,(I have the output on the screen set to show mph, but the device internally logs everything in metric units).
There is an earlier post regarding an H16 "pushed well past the 20 mark."
I do not believe that. 
It is well known in the tuner & racing camps that there is no substitute for horsepower. In order to go faster you need more power, lots more. It is not a linear graph. With wheeled vehicle, it doesn't take that many horses to push a light car to 100 mph. It takes hundreds of HP to double that speed to 200mph.
The situation with a boat is worse, due to the density of water creating much more resistance than the rolling resistance of tires. This is the reason it is easy to go 18mph in a Cat, but breaking 20 becomes problematic. We all talk about "powerful" sail plans, but in reality they don't generate very much, limiting speeds to around 20mph in conventional Cats. My 20' Mystere could do it in rougher water than the 5.0, but I never did get it to make 22. The oft repeated phrase that Tornado's are theoretically capable of 35 kts is a pipe dream.
The move to foiling boats removes much of the drag, hence the speed gains.<em>Edited by Edchris177 on Nov 04, 2014 - 06:28 AM.</em> [/quote]

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