I lived in the Seattle area by Sea-Tac airport in the 60s and 70s before turbine hydros were on the scene. It was the best of times.... you could hear the Allison and Merlin powered boats 15-20 miles away from the lake. When they had a 10-boat flying start was really something to see 10 hard chargers heading for the starting line at 150+ mph!
Haven’t watched hydroplane racing in a long time. Didn’t realize the pistons powered boats were competitive with the turbine powered boats. That’s awesome.
@@dizzyrain985 the CFM from 20+ psi boost is huge, here is a video of a small turbo and how much air it can move ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-dDncgYH5q7A.html
@@imoovabull6042 That's crazy to think that there is a void of air when the boat is going at that speed. I have always wondered the volume of air consumed by a turbo at different psi.
Well when you take the latent drag coefficient and compare it to the resonance frequency of the engine you find the critical speed in which the turbo reaches its max turbine induction howl, the buffeting of the air through the intake plenum creates turbulent pockets which reduce volumetric efficiency. Dont even get me started on the compressor stall one might encounter when decelerating from load of the waste gate solenoid is shorted out by water.
Ok ok, how much power does a twin turbo Allison like this make? I’ve read that the Rolls Royce Griffon replaced the Allison as the preferred piston engine? What kind of power does the Rolls make?
Shaft-driven helicopter turbines have more low end power. Past 130mph or so the acceleration suffers heavily. Twin turbos have the upper hand in that department.
Man...I wish they ALL would go back to the Allison V-12 and or V16’s alike. love the sweet sound of the torque and big V12 motors. Never liked those stupid turbine, especially here in San Diego.
Just in case you don’t know but all ya all is crazy. People think road racing motorcycles is crazy but they ain’t seen crazy until they have seen this video. Well done. :)
This video just popped up in my feed. That moment caught my eye too. I had to go back and watch it a few times to figure it out. If you use the < and > keys on your Keyboard, you can go frame by frame. And if you watch, it is nothing but a simple backfire. First on the left bank, then two frames later, on the right bank. Which gives it that double percussive "buh-bump" sound.
att 0:56, is that an viper engine ?? smart choice havin em turbos in front in the open sucking in som fresh cold sea water steam to boost it upp some more.
I’m not insulting in any means, but a half a million dollar craft and a 10$ steering wheel. 😂 The video was awesome to watch, thank you team for allowing us to take an honored seat. I liked the adventurous part where ole’piston-pusher passed the turbine boats and then they tried to jump back into the game. Tried and true!! Seattle Lakefair would be an awesome opportunity to visit!
@@linusbosse285 - Of course they know what they are doing. From an airflow point of view, sharp-edged stub inlets cause fluctuating unwanted turbulence that disturbs the airflow. Look at the inlet orifice of any air-breathing engine and you will find that it is air-streamlined. (Gas-flowed). I merely suggest a possible reason why the other boats are keeping ahead...
The fact that the exhausts aren't canted at the same angle is really bugging me. Edit: I now see that the entire turbo setup is asymmetrical lol oh well
IMHO it's probably a good mix of both, their isn't as much regulation for boat design and power plants in boat racing as there is in say F1 or NASCAR so the engineers have some more wiggle room but at the end of the day you are still dealing with the unpredictable nature of the water surface which requires a skilled racer to overcome at these speeds
