Hello Frank,
Are you sure that your jets did not suck up any dirt?
As I remember in one of your video’s you mentioned that there was dirt in the pump.
I did damage one impeller but this was because I was doing beach starts.
The beach was full of shells and small rocks!
The bushing at the back of the nozzles are for me fine.
However I can see them getting damaged when running the motor dry to long
I’m a lite person (65kg), and can get my short 190cm surfboard up to around 30 km/h. (on 6P6S)
Funny enough the board got faster when I made it shorter.
Before it was 220cm and no way I was even close to the 30 km/h.
Also. It looks like you placed the jets pretty close to each other. Could this cause your board not to get up to speed as both pumps are sucking water away from each other?
To bad Mark does not respond to you anymore! Maybe your emails are going into his junk box?
Like me. I never check it!
Stay safe! Have fun!