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5:00
09-16-2019, 02:48 PM
I moved my boat from 257' above sea level in Virginia to 800' above sea level in South Carolina. Only a difference of +543 feet.
We used the same settings, suck gate, rope, board and everything else from the other lake including our two friends we usually go out with. Okay I have gained a few pounds but only a few. No problem with pulling up so no need to change prop.

I was the first to be pulled and my wife who has pulled MANY times was having difficulty getting the wave to form initially but not too bad. Once it did we had at least a 3' killer wall which was our highest ever. Plenty of push but only 1/2 to 3/4 length we had before. Okay I know how to fix that.
Does the altitude really change things that much or am I just imagining it?

tre
09-16-2019, 07:26 PM
Strange. Sounds like something changed. I'd guess you were going too slow. Assuming you were using perfect pass, it would get you to the correct speed regardless of altitude. I'd say there is either more weight in the boat or the perfect pass settings changed to a slower speed.

larry_arizona
09-16-2019, 07:51 PM
500 feet of altitude should not be noticeable, however on any given day, density altitude can change 1000-2000 feet plus actual elevation.

Just an example. Temp, barometric pressure and humidity can cause large swings in density altitude day to day. Engines don’t care about elevation, they care about density altitude.
https://uploads.tapatalk-cdn.com/20190916/e08d1f6d10ac1c8fce97fc56a6aead7e.jpg


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MLA
09-16-2019, 08:12 PM
Is the new lake shallow?

sandm
09-16-2019, 08:18 PM
Is the new lake shallow?

that was my first thought.
can't really think that 500ft would make a huge difference in performance

tre
09-17-2019, 01:49 PM
I was thinking shallow lake too until I realized he said it was the tallest wake he ever had, just not long. When we go through the shallow spots in our lake (< 12' or so), the wake is much shorter with mush less push but the length does not change. I don't think his wake would be that tall if the lake was shallow.

5:00
09-18-2019, 11:45 AM
Thanks for the input. Probably a setting difference I'm not catching. We haven't been out since last summer. No big deal, we are used to adjusting things but I was just wondering if that was it.

Yes we are using PP with the GPS mod and calibrated to an external GPS for the PP.

I actually dumped about 1/4 of the water from the rear bags and it did help a bit with length and no loss in push. My buddy was surfing back while I emptied the rest of the ballast and the wave lasted much longer than normal while doing this. Magic lake, IDK? I think I just need to add more weight than before in the bow.

On the depth we were just over 50'. For a man made lake it is crazy deep compared to where we used to be. I saw plenty of over 100' and average about 50'. It was a new lake to us so I was constantly watching my depth. All of the trees, branches and stumps were removed when the lake was built so the bottom is pretty smooth.

The water is VERY clear instead of the brown water we were in. I don't imagine that would be a different density though?