06-21-2009, 08:32 PM #1
New speeds but speed lacking..... thoughts?
RXP speeds were 74mph at 8440 rpm, seems slower than expected
15/20 with -2 pitch
RIVA VTS Extension Rod
Water temp unsure (78+ tho)
Air temp 95-99F
So i dont have the Riva Wedge or Reduction nozzle installed yet
06-22-2009, 06:07 AM #2
That's def low speed for that set-up.
Make sure sponsons are up at least to middle, fill ride holes, check trim is working, rev gate is modded etc, Nozzle matched up to new output of pump... maybe a ring smaller would show what is the problem is.
Is the prop out to a 15/22 now?
06-22-2009, 11:24 AM #3
Wow, thats a puzzler ... I had basically the same setup last year and ran 80 - 81.5 depending on weather. I would check the troubleshooting thread for ideas and things to try ... even at 8400 rpms I could usually hit 80 on GPS. I varied rpms by swapping nozzle rings a bit.
06-22-2009, 11:32 AM #4
- Join Date
- Dec 2006
- Crest Hill, IL
Is anything dragging?
06-22-2009, 12:19 PM #5
06-22-2009, 12:20 PM #6
ski pulls like a beast.... not sure...
ride plate holes are filled
sponsons are on lowest setting
trim is not adj as riva messed up my ECU so not sure on spot but appears middle or +1
06-22-2009, 12:28 PM #7
Any other symptoms like water in the hull or anything? What is the speeds & history of the ski? What I mean is what did it run before the mods, etc.
Hate to say it, but from what you described so far, it sounds like the intake grate inserts pulled out and the grate is dragging ...
Last edited by Vern; 06-22-2009 at 12:29 PM. Reason: oops
06-22-2009, 12:33 PM #8
prior speeds were about 71 with no riva ecu and no xcharger
so as of now, only +3 in speed
i did notice some weeks ago if i left ski on the beach that it was like half flooded... unforunately only a manual bilge..... i assumed carbon ring but last ride didnt show any water in hull but then again i was flying around and back on trailer...
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