It doesn't work opposite. Airplanes have been doing this since 1963. It is called a Turbo Normalizer. It is simply a different way of adjusting the wastegate. All the other components work exactly the same. How many times are you going to ask the question?
Why did Doo choose to make their turbo work opposite to how a turbo normally works?
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Mike270412
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I used to think the Freak was just a drunk. Now I starting to think he may be mixing chemicals with his home brew. Have fun with the ladyboys.
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Longhairfreak
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Longhairfreak
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So I'm thinking by weeks end someone will have a fix so this sled can run constant boost instead of gradual?
maxwell
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im confused as to why anyone would care what a mountain sled does for boost at 0-6000ft? generally riding is between 6000-10000 and its making boost in those ranges
pfi572
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For years sledders talked / wanted just enough boost to keep stock power at elevation !!
Wouldn’t it be awesome if the manufacturers would do this ?
Soooo ................. ???
Keeps everyone entertained I guess ?
Good on BRP as I think it’s awesome what they did .
banditpowdercoat
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Why? For reliability thats why. If a engine is built to produce 165HP at sealevel, BUT, do that reliable and all day, every day without issues and without over stressing the engine. Then, when you add boost per elevation, this, like was already stated is a HP Normalizer. It is letting the engine "SEE" Sealevel air pressure, at elevation. This maintains the HP level the engine was designed for and does not stress the engine in any way different than running at sealevel N/A does.
Y;all are stuck on the, I can make X HP numbers. Well any other turbo out there is Atmosphere referenced. That means, As you climb, the the turbo produces the same PSI that you set down low.
BUT, the atmosphere pressure drops. 14.7PSI at sealevel, 10.6PSI at 8000ft. SO ya lost 4PSI at 8000PSI, Boosted or not..... But This new setup compensates and ADDS boost at the same rate the earth looses it
Another way to see it, A 210HP @ Sealevel boosted sled is....... approx 165HP at 8000Ft!! Stock HP up high, but stressin the crap outa it when your cooking your Chef-Boyar-Dee in the parking lot.
Y;all are stuck on the, I can make X HP numbers. Well any other turbo out there is Atmosphere referenced. That means, As you climb, the the turbo produces the same PSI that you set down low.
BUT, the atmosphere pressure drops. 14.7PSI at sealevel, 10.6PSI at 8000ft. SO ya lost 4PSI at 8000PSI, Boosted or not..... But This new setup compensates and ADDS boost at the same rate the earth looses it
Another way to see it, A 210HP @ Sealevel boosted sled is....... approx 165HP at 8000Ft!! Stock HP up high, but stressin the crap outa it when your cooking your Chef-Boyar-Dee in the parking lot.
Pistonbroke
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building on this, does everyone know what the definitions of absolute pressure and gauge pressure are? Herein lies the holy grail of spooly bois and elevation...... oooohhhhmmmmmmmmm
tmo1620
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I bet it also has something to do with emissions, more power down low, more fuel burned, same exhaust would probably equal higher than allowed emissions
skegpro
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Bingo.
greenthumb
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The mcx kit I had on my Yamaha 10 years ago was designed to compensate for altitude and deliver constant power. It had an electronically controlled boost tee. It's not a new concept for snowmobiles.
pfi572
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No it’s not but sure is for a factory supplied 2 stoke turbo system .
cdnredneck_t3
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I'm not a Doo loyalist by no means. But I think this is an awesome advance. Very close to if not the same throttle response as NA. No tinkering with clutching until over 8000ft. Factory warranty. Even if you don't ride a Doo it will push Cat and Poo to up their game. We all win.
For simplicity Linghairfreak, it is set up to maintain 14.7 psi absolute Manifold Air Pressure. A normal spring waste gate will open at a differential Pressure because you have boost pushing on one side of the diaphragm and atmosphere plus a spring on the other. If it has a 5 psi spring it will take 19.7 psi to open at Sea level or 15.7 at elevation.
For simplicity Linghairfreak, it is set up to maintain 14.7 psi absolute Manifold Air Pressure. A normal spring waste gate will open at a differential Pressure because you have boost pushing on one side of the diaphragm and atmosphere plus a spring on the other. If it has a 5 psi spring it will take 19.7 psi to open at Sea level or 15.7 at elevation.
Dazzler
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My 2011 Assault was set up similar. The boost was set at 6psi sea level, I would see as high as 9-10 psi where we typically ride.
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Longhairfreak
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the biggest difference is Nitro''s suck and factory turbo experts are awesome.
canuck5
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I have to agree with this a true mountain sledder what’s peak performance up top. I also think the biggest restriction is octane. These high performance two strokes already require 91 for the compression ratio. Even at 4 psi down low if I was a betting man someone ripping a heat soaked sled across a farm field in wot long enough could get it to detonate. We will know if it’s only ever offered on the summits.
Caper11
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Who cares!!! A manufacturer offered a two stroke turbo from the factory, and it works. 
Ive been happy on my NA sleds for years, and never had the desire to own a turbo sled until now.
Ive been happy on my NA sleds for years, and never had the desire to own a turbo sled until now.
skegpro
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Don't even need a turbo to do that.lol.
Dazzler
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