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400R power

Old 06-28-2020, 09:46 PM
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Question 400R power

I have a question for the outboard pros, a little background first: I have a 2020 Berkshire 27' Tritoon with twin 400Rs and I am running 76mph @ 6,850rpms with 5 people aboard, barometer at 29.7, and 80% fuel, turning the props inward, jacked up pretty high and trimmed out at 23 degrees. The boat really handles like this in the lake slop.
Last week when the barometer was 30.6 and we had a nice 8" chop, I ran a solid 80mph with 60% fuel, turning REV-4-21s (labbed and pitched to 21.9) @ 7,000rpms, just myself aboard.

Now for the question: I am planning to go to the LOTO Shoot-Out in late August and run my boat in the twin 400R toon stock class. The current record is 78mph (but I think the guy had flashed ECUs). My lake is a slow lake because of the its 794' elevation and always humid. LOTO is 659' elevation (a 135' difference). I heard that the 400Rs compensate for elevation and produce more boost accordingly and therefore I would be running the same speed at LOTO that I am running on Smith Mountain Lake! I find this hard to believe Can someone set me straight.
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Old 06-28-2020, 10:19 PM
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Hmmmm, don’t overthink it! Come to LOTO for Shootout week and have the time of your life!
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Old 06-29-2020, 09:55 AM
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Doubting that 135 feet of altitude change is going to impact anything much.
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Old 06-29-2020, 10:33 AM
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Wouldnt humidity and temp affect it more than 135 feet of altitude?
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Old 06-29-2020, 11:44 AM
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I think you may be right there. I have a neighboring lake that is 250' elevation as compared to my 794' elevation and it makes a 3mph difference. ... but 135' is probably no big deal as compared to temp, barometric pressure and humidity. Thanks for the reply
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Old 06-29-2020, 11:44 AM
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Yep, makes sense to me
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Old 06-29-2020, 12:31 PM
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Humidity will affect all the players , can you hit those speeds from a rolling 45 mph start and only going 3/4 of a mile?

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Old 06-29-2020, 07:58 PM
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Originally Posted by JaayTeee View Post
Humidity will affect all the players , can you hit those speeds from a rolling 45 mph start and only going 3/4 of a mile?
Is the rolling start 45mph or 30mph? I know the course is only 3/4 mile. I guess I had better practice LOL!
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Old 06-29-2020, 09:15 PM
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Originally Posted by Spectre Man View Post
Is the rolling start 45mph or 30mph? I know the course is only 3/4 mile. I guess I had better practice LOL!
45 just don’t break 50
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Old 06-30-2020, 06:59 AM
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Originally Posted by JaayTeee View Post
45 just don’t break 50
Thanks JaayTeee ... now that I know it's 45 instead of 30, it makes a big difference to me. I pretty confident I can hit 80 in 3/4 mile from a 45 start. My boat is light and I have a wicked punch at 45! A friend suggested I try Lab Finish Bravo1FS props for a better top end than the REV4s?

I'm pretty sure that most of my competition (twin 400R pontoon class) are using flashed motors - I'm not. When I'm running in the high 70s, my pontoon almost feels like my old Skater .... it kind of sponson walks a bit - probably due to turning the drives inward. It really feels good.

Thanks for your help
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