My misstake.
You mentioned “13s8p battery 60amp bms”
I was thinking that your BMS was 60amps 
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What bms would you recommend ?
Would a 180kv 80mm motor be better?
I dont believe the impeller in this jet is efficient
@JZILVIA 360kv on 13s so around 18000 rpm , on your video it doesn’t sound it is running at that speed
The problem is with your esc you cannot see the rpm , or what is left of it and I think the water intake has too much angle compared to what is on the market
Proven built : sss motor 56mm with 50-55mm impeller , you need 2-3 of them
80mm impeller with a 80mm outrunner or 100mm inrunner
For the kv calculation, speed desired knowing impeller have a ratio of 1or 1.2 ( diameter vs pitch and pitch x rpm= speed or pressure …)
Voltage drop of the battery , you can take 3,6v as a average
Rpm drop of the motor under load : you can take - 40%
So on a 13s battery with a sss 56mm 360kv you should take a impeller of 52mm to :
13x3,6 x360 x60% = 10000rpm
Which is not enough for it and why 600kv is better
Now with 80mm : a 300-360kv outrunner 80mm should do the job but they are hard to find
Esurfboard are nice but price vs fun is not so good , you take a large board ( inflatable) with a 63mm outrunner and a good prop , for 1/4 of the price you have more fun
Nice car 
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Alexandre nails it every time.
83100 water cooled is a good start for 70~80mm 3-4 bladed impeller.
There’s a Chinese MHZ 7455 Scorpion clone, I think its goes by the model “9096” on Alibaba, if you’re looking for a powerful outrunner it should be in the 2.2~2.5kg range.
Chris Green’s early jet design:
Thanks for the info ^^^.
So basically I would need to ether up the motor to a rare 80mm or down size the jet to a 53?
1x53mm jet is unlikely to push a 3m board with total weight around 100kg and the rear of the board isn’t really wide enough to house 2 jets.
Think I will likely up the motor size and see what it can do
The jet lift is maybe only 10mm
@Alexandre thanks the car has been a restoration project since 2016 but it’s at a point I’m happy to just drive it and has now freed up enough time for me to play jet boards 
Yes it would perform a lot better , just need cooling , need to be mounted on a big plate that will hold it and cooling it
Watercooling will go on the plate
Some 80100 are watercooled , you may want to ask APS for it with 350kv
Tp100 looks exciting in 540kv
No doubt about the TP100, but then you need a very expensive ESC like MGM, or the biggest Flier ESC (still questionable).
I assume you’ve already watched this one,
The guy is using a TP100 along with APD UHV 400A Esc on 18s (fatal voltage)
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Here we go , nice , a tp100 290kv on 18s with a 80mm MHZ do the job
90mm DIY jetpump
Greetings Frank
Very nice as always , may I ask how do you figure the blade angle and diameter of the nozzle ?
I have it no angle 
I feel it 
I make 40ty year rc models, rc Heli, and boats and I have the Graupner 50mm jet pump only bigger built 
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@JetboardCologne That looks great You have done a an amazing job with that the impeller is my other target that I need to look at as I’m not convinced 6 blade prop is efficient looking at space between blades and pitch.
I’ve been looking at other available motors and it seems you can’t get 300kv -500kv in an 80mm without custom work. So Im Thinking of requesting a 400kv 83100 be made around 7-8000w, what do we think?
I would really like to just throw money at a tp100 and call it a day but sadly without redesigning the dropped section in the board it just won’t fit.
Sadly my last outing resulted in me drowning my 400a esc so I’m on the bench till I get parts back. (When a hatch is described as waterproof I really wish it actually was)
And that would be OK on a flier 400a With water cooling?
Have you seen this build already?
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I don’t recommend buying this MP motor.
I was tempted to buy one myself too since it seems to be a much cheaper version of the TP100, it’s basically a Chinese clone, however, longevity and quality-wise is incomparable to the TP.
I know I’ll buy a TP in the future, just by looking at the magnetic wire on that beefy motor you know it’s built for big amps.