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Discussion Starter · #1 ·
hello, [email protected] or any one who has tuned a jacuzzi wj! 73 jemcraft/southwind SJ approx 500hp jacuzzi wj custom ride plate b/c htp cut impellar went 69.9mph with original jacuzzi diverter and ridin wet! So i went to the adapter ring and std droop with 5deg up wedge made a pass in mod chop water @ ft cobb and the boat slowed to 66.5mph and these are garmin gps passes! just lookin for some tuning help! i have been told so many things whats right and wrong???
 

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I'm far from an expert at seting up jetboats, but I believe wedges are used to fine tune the way a boat rides. And without running it 1st with the droop you don't really have any way of knowing whether or not wedges may be helpful. Not to mention, 5* up seems like a lot. But again, I'm just an enthusiast, not an expert.
All the folks that I've spoken to about the subject STRONGLY suggest an incremental approach.....one change at a time.
 

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Discussion Starter · #5 ·
one change at a time for sure! made this one major change and was hoping for 72/73mph and it went the other way! open to any jacuzzi info anyone may have!
 

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As TX75 said that wedges are for tuning! And with some boats things just don't work the same as with other boats! I would start by removing the wedge and see if that makes any difference! And if that doesn't work contact Timinator or Tom(JBP) or someone in the know and they will help steer you in the right direction! Good luck! WT:)devil
 

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The droop you put on has 6 degrees up already built in it. By adding the 5 degree wedge you now have a total of 11 degrees up nozzle. That is way too much for most boats. Try it without a wedge and go from there.
Duane HTP
 

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Our WJ adaptor basically allows Berk style "bolt ups" to be used to modify Existing WJ Bowls (large 4 bolt pattern) Unless the bowl exit side has been milled (lower picture) I would "baseline" this boat with no wedge and start from there as said above . My Miller 18' just shy of 80 out of the box with only "up" being the inherent Dominator and a smidge of Dominator "mini trim" (about 4* of up/down on the fly ) Tom

 

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Discussion Starter · #10 ·
Thanks duane and tom i will try this when weather permits and post the results! how critical is the other .5" on the bowl exit? rideplate adj which is correct down pushes transom up or up lets boat pivot back onto plate? should i try putting a loader in? tom are you running a loader in the miller set-up?
 

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Thanks duane and tom i will try this when weather permits and post the results! how critical is the other .5" on the bowl exit? rideplate adj which is correct down pushes transom up or up lets boat pivot back onto plate? should i try putting a loader in? tom are you running a loader in the miller set-up?
5* is significant , lose the wedge for now , I'd start with the Droop only, put the ride plate at 2 to 4* up and go out make a couple back to back passes (no "stuff"& driver only) and have someone observe the boat "attitude" from shore (photos are always nice) Re the loader , we no longer sell WJ loaders of any sort particularly the "River racer angle iron type" , will have a new Dub J unit in the early spring. Mine has a stock rock grate, AA pjx Impeller and some bowl work Tom
 

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Discussion Starter · #16 ·
yes i cut it off flush! but still lacks .5" to get the speced 4.5? just out workin on 5* removal looks like reverse section of the nozzle is going to create lots of drag? anyway to minimize it if so!
 

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Discussion Starter · #18 ·
Tom i will take some today when i get home from the ole 8-5! so you can see exactly what im workin with ride plate in all!!!!
 
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