03-25-2010, 04:04 PM #1
DO NOT blueprint the grate to the transom plate on a SHO!!!
After hearing good results from this on the FZ's, I opened up the sides of shoe section of the grate to match the ID of the transom plate & got nothing but an incurable buck. It allows more water to enter the pump & causes it to overstuff. The pic shoes how it looked before I opened it up.
After it happened with the stock ECU with a modded R&D plate, I put on my modded stock plate(less angle), a shorter prop, bigger nozzle ring, reflashed ECU & put the stock pump cone back in. It still bucked at the same speed(69mph), and felt real loose & sqirrely as the speed went higher. I could install pressure reliefs, but IMO that's a bandaid & it might start to happen again at higher speeds...not woth the risk.
I guess Riva made it like that for a reason.
03-25-2010, 04:56 PM #2
Good info Mark. I was kind of baffled whe Eric told me about it. Glad you found the culprit.
03-25-2010, 05:14 PM #3
03-25-2010, 05:16 PM #4
03-25-2010, 05:19 PM #5
I still don't know what "blueprinting" actually means. One day I will muster up enough courage to ask...
03-25-2010, 06:20 PM #6
03-25-2010, 06:27 PM #7
When you balance and blueprint an engine, you simply balance the reciprocating assembly and then measure every clearance and record it on paper, just as a blueprint is on paper..
You then have a blueprint of your engines clearances for future reference.
03-25-2010, 08:04 PM #8
Wonder if an adjustable grate (like a TBM) would be able to cure this problem with the ability to "load" the pump more by lowering the scoop?
Too bad they only make them for the FZ-series skis presently.
03-25-2010, 08:09 PM #9
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- Southern Florida
03-26-2010, 08:26 AM #10
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