10-09-2006, 06:49 PM #1
Need some help with adjust a thrust
I know this is the seadoo forum but there are a lot of experienced and knowledgeable folk over here. I've tried the kawi section but I've had no replies in 3-4 days. My question is in regards to boring an exit nozzle on a pump. My stock exit nozzle diameter is 82mm. While tuning the adjust a thrust I found I ran my fastest WITHOUT a shuttle. In fact 1.2 mph faster than the shortest shuttle and shortest bolt and I also had MUCH better acceleration without the shuttle. Without the shuttle in I gained a total of 2-2.5 mph from the impeller. So now I'm trying to figure out how to get the use out of my AAT. How much should I bore so I can get the low end of a big exit nozzle and use a shuttle to provide the top end? I was thinking of going big because I currently run best without a shuttle and have tons of room to grow by adding the shuttles in to provide the top end thrust. Is 3 mm too much? Where should I go to have the work done? A machine shop? Any opinions and comments are appreciated.
10-10-2006, 10:45 AM #2
Just keeping this towards the top for you.
Nobody must know how to help you apparently
10-10-2006, 11:00 AM #3
10-10-2006, 11:22 AM #4
Aaron, any machine shop should be able to bore the nozzle. I would start at 2mm and see what happens.
10-10-2006, 11:42 AM #5
Thanks for the feedback. I will bore the nozzle and retune. In general how many rpm's does 1 mm give you? Or is it different for every situation?
10-10-2006, 02:55 PM #6
On my RXP, 1mm equals between75-100 rpm. The larger you go, the harder the hit off the line. But you obviously sacrifice top end a little. Set it for what you want most. Most try to find a happy medium. With the RXP/T we have to deal very carefully with the rev limiter or the ecu will shut it down, so be careful not to overrev your ski.
Hope this helps.
Last edited by BDNJ; 10-10-2006 at 02:58 PM.
10-10-2006, 06:09 PM #7
Thanks, that's good info. I took the nozzle to a machine shop and they're taking out 2mm. Even though I can't find any specific info on a kawi, the info I've searched for and replies I've gotten in this forum will most definitely help forecast the end results. I will post up how things went when I get it back on the water. Thanks a bunch guys!
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