Thread: Some Speed Testing, Finally
04-24-2007, 05:31 PM #1
Some Speed Testing, Finally
Well, I finally got around to speed testing some today and I wish I had some better news to report.
The ski has 6 hours, 3 bars of fuel, water temp about 60, air temp mid-70's, windy, and choppy. All testing done with a Garmin e-trex Legend.
First, stock runs. With the wind 67 (best run of the day, probably before everything got heat soaked), against 65.7. Back up runs could not reach 67 again, 66.7, 66.8 best. About 66.1 average.
First mod, iridium plugs. By this time the wind had died a little and the best with wind speed I could get was 66.6. Runs in the other direction stayed about the same. Just to make sure the plugs did not slow me down I switched back to stock and the speed results were the same. By this time the fuel buzzer was going off, but speed did not change.
Next I pulled it out of the water and put the Riva Sponsons on. The first setting I used was all the way up and back. I was a little disappointed as I thought this would be the fastest position. Average 2 way runs with this setting were about .3-.4 mph slower than any other run. Average speed was about 65.6, 65.7.
Trying to get in one more test before rain I moved the all the way to the front and still all the way up. This position seemed to handle a little better but it again scrubbed off a little speed. Runs in this position netted about .5 mph slower than stock sponsons.
That is as far as I got before the storms came.
Here are my observations:
1) It's slower than I though stock (although I did check my oil again and it way over cold fill when it was hot).
2) Iridium plugs did not add anything at this power level. Perhaps they will show more gains as boost and fuel levels increase. I have had good luck with them in the past as my cylinder pressure increased(in a car).
3) In the positions I was able to test the sponsons scrub speed, not add. I would like to try some more positions as soon as I can. I will try Skips setting next. If any of you have seen any speed gains I would love to try your settings, if you don't mind sharing.
Next I will try to get my oil level straight and do some tuning on my bypass valve, unfortunately it won't be until next weekend
04-24-2007, 05:33 PM #2
Forgot to add I already have the pump wedge and rideplate sealed up.
04-24-2007, 08:45 PM #3
- Join Date
- Sep 2006
- S. Florida
Thanks for the writeup.
Does you ski cavitate at all on takeoff or coming out of hard corners?
04-24-2007, 09:04 PM #4
None at all, it hooks hard and goes...dead stop or turn
05-03-2007, 07:02 PM #5
- Join Date
- May 2007
so the riva sponsons were slower? i have set on too. im looking for topend only, should i rip mine off then and back to stock?
05-03-2007, 10:16 PM #6
05-05-2007, 08:17 AM #7
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