Important >>> Ski-Doo Summit 850 TURBO OEM at long last!!!!!!

Post number 92 has been selected as best answered.

Escmanaze

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Very interesting to see the mixed reaction on both sides. Apparently, you either ride at elevation and this is heaven sent, or you don't, and you kinda dont' really get what all the fuss is about.
 

Slednut84

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Dec 23, 2014
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Props to Ski-doo on this one. Don't forget there's only so much cylinder pressure you can run before you require higher octane than you can get at the pump. I'd guess that level of pressure brings you to 165hp on the 850 leaving a little safety margin for variability in fuel.
 

BeartoothBaron

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Being a pilot, I have to wonder if Doo is talking about 8000' standard day (so, temp around freezing at 8k), or more typical conditions (maybe 0ºF). I'll not get into too many boring details, but it could be it'll hold 165HP even over 10K on a cold day (although the NA sled would also be making 8k' equivalent HP in those conditions). Basically, if they're going by 8k' standard day, most riders will be seeing 165 up to 9/10k, BUT, Doo's material just says "up to 8000 feet." They could just as easily be basing their numbers around colder than standard temperature; all the sled manufacturers are pretty quick to use "typical conditions" over standardized conditions that are required for SAE, DIN, and such HP ratings. Regardless, the typical rider will see the 40HP advantage; if you ride in AK or the UP, you know who you are, and probably won't spend the extra money. They make it pretty clear it's 40HP above 8k (give or take).

Obviously, everybody would have liked to have seen more HP, but you've gotta credit Doo for finally putting out a factory 2S turbo. Also, would have been nice to see rated HP to a higher elevation, but I'm guessing I know the reason why it's only to 8k. To maximize responsiveness, they likely used as small a turbo as they could. Small turbos spool quickly, but encounter surge at higher pressure ratios. To maintain the same HP as elevation increases, you have to increase pressure ratio, so they had a choice of either putting on a bigger turbo and losing response or limiting the turbo more. I'd say they made the right choice. Guys who run chutes up above 10k will be disappointed, but for everyone else, it's just going to be better to ride. To bridge that gap, I think a VGT or twin-scroll turbo will be needed. That should allow you to get the kind of pressure ratios you need without losing response (possibly improving it). Only question is whether there's an off-the-shelf turbo that would work. Ten years ago, definitely not, but now that we're seeing more and more small automotive turbo applications, there may be a good match already out there. Maybe couple that with a snow-to-air intercooler for really big boost! Could be dreaming there...

Anyway, looks like a really promising product! In a couple years we could be seeing 180-200HP above 10k, <450lb. It'll take a motor and chassis designed from the ground up for a turbo to maximize power and minimize weight gain, but the gauntlet has been thrown!
 

sno*jet

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how would a guy modify the system to not turn down the fun past 8k, that is the question.
Yamaha makes 55 more horse than this thing at the top of the rockies. And known to be reliably cranked up much further.
 

caper11

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Nov 2, 2008
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It is not 40 HP more. It's the way they are marketing it that makes you guys think that. It's only 40 HP more than stock of they are side by side at 12,500'. I talk to Tony about it tonight. This is a huge gimmick and only worth it if you ride over 10,000'. It's the same sled as stock until you get over 8,000'.
Wrong.
 

Escmanaze

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how would a guy modify the system to not turn down the fun past 8k, that is the question.
Yamaha makes 55 more horse than this thing at the top of the rockies. And known to be reliably cranked up much further.
Did you just put "Yamaha" and "the rockies" in the same sentence? You must live in a different set of Rockies than I live in. Here in Utah at least, Yamaha couldn't possibly be more dead and irrelevant. Nobody in the Rockies cares how this sled compares to a Yamaha.
 
Mar 13, 2014
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Being a pilot, I have to wonder if Doo is talking about 8000' standard day (so, temp around freezing at 8k), or more typical conditions (maybe 0ºF). I'll not get into too many boring details, but it could be it'll hold 165HP even over 10K on a cold day (although the NA sled would also be making 8k' equivalent HP in those conditions). Basically, if they're going by 8k' standard day, most riders will be seeing 165 up to 9/10k, BUT, Doo's material just says "up to 8000 feet." They could just as easily be basing their numbers around colder than standard temperature; all the sled manufacturers are pretty quick to use "typical conditions" over standardized conditions that are required for SAE, DIN, and such HP ratings. Regardless, the typical rider will see the 40HP advantage; if you ride in AK or the UP, you know who you are, and probably won't spend the extra money. They make it pretty clear it's 40HP above 8k (give or take).

Obviously, everybody would have liked to have seen more HP, but you've gotta credit Doo for finally putting out a factory 2S turbo. Also, would have been nice to see rated HP to a higher elevation, but I'm guessing I know the reason why it's only to 8k. To maximize responsiveness, they likely used as small a turbo as they could. Small turbos spool quickly, but encounter surge at higher pressure ratios. To maintain the same HP as elevation increases, you have to increase pressure ratio, so they had a choice of either putting on a bigger turbo and losing response or limiting the turbo more. I'd say they made the right choice. Guys who run chutes up above 10k will be disappointed, but for everyone else, it's just going to be better to ride. To bridge that gap, I think a VGT or twin-scroll turbo will be needed. That should allow you to get the kind of pressure ratios you need without losing response (possibly improving it). Only question is whether there's an off-the-shelf turbo that would work. Ten years ago, definitely not, but now that we're seeing more and more small automotive turbo applications, there may be a good match already out there. Maybe couple that with a snow-to-air intercooler for really big boost! Could be dreaming there...

Anyway, looks like a really promising product! In a couple years we could be seeing 180-200HP above 10k, <450lb. It'll take a motor and chassis designed from the ground up for a turbo to maximize power and minimize weight gain, but the gauntlet has been thrown!
Don't do it i'm saying to myself...But I do enjoy arguing turbo misinformation.
 

Rotax_Kid

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Nov 29, 2007
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You really have to give props to Doo - this is a great package. Turbo looks very centralized, and they would have had to meet both EPA and Noise emissions with this build. That aren't easy things to meet. We also have no idea what other applications this motor has, as you could be certain there are more than we know to spread development costs out.

Could have they built more power with it? Certainly, but for the 99% of the population out there who will fill it with farm gas, drive it at all altitudes with the throttle to the bar, and not have any warranty issues, what else could you really ask for? For a guy who lives in the flats at a relatively low altitude, this is a fantastic option. I used to build some fairly extensive mods. Life has gotten busier and for me to drive 8-12 hours for good riding, all I want is the dam thing to run for 3 days at a time without an issue and not need to tour a drum of 110 around. For guys like me, this is a killer option.
 
Mar 13, 2014
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You really have to give props to Doo - this is a great package. Turbo looks very centralized, and they would have had to meet both EPA and Noise emissions with this build. That aren't easy things to meet. We also have no idea what other applications this motor has, as you could be certain there are more than we know to spread development costs out.

Could have they built more power with it? Certainly, but for the 99% of the population out there who will fill it with farm gas, drive it at all altitudes with the throttle to the bar, and not have any warranty issues, what else could you really ask for? For a guy who lives in the flats at a relatively low altitude, this is a fantastic option. I used to build some fairly extensive mods. Life has gotten busier and for me to drive 8-12 hours for good riding, all I want is the dam thing to run for 3 days at a time without an issue and not need to tour a drum of 110 around. For guys like me, this is a killer option.
I could ask for a kit to put it on to my 17 so there!
 

ntm_08

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Yamaha sidewinder with a more expensive 4s boosted engine, cost the same as a stock 850 non boosted doo. With the boosted doo at +3000$. That's a lot of margine I would say :coffee:🤑
 

sno*jet

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Did you just put "Yamaha" and "the rockies" in the same sentence? You must live in a different set of Rockies than I live in. Here in Utah at least, Yamaha couldn't possibly be more dead and irrelevant. Nobody in the Rockies cares how this sled compares to a Yamaha.
think what you like under that tin hat
 

Shortline

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Feb 24, 2016
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Lol who else was waiting for chadly to show up with his .02 cent comments. Stick with your poo buddy I don’t think anyone here cares
Me for one! No better entertainment than Chadly on this forum. Worth the price of admission. In his defense he's a super nice guy and can take it as well as he dishes it out.

Just love that he calls everyone simpletons only to explain it all wrong himself. Can't wait for Poo's response to Doo just to watch Chadly "educate" us.
 

PaulAnd

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Oct 17, 2010
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The only downside I see in this is the warranty,
If we can spring order this package for 2021 in 2 months it can come with a 4 year warranty for the same price


Sent from my iPhone using Tapatalk
 

goridedoo

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The only downside I see in this is the warranty,
If we can spring order this package for 2021 in 2 months it can come with a 4 year warranty for the same price


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A 4 year warranty with snowcheck hasn’t been confirmed.
 
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