2022 Polaris Boost Math

[fj40]

My math was 10% more than doos 850T (165HP) @ 8000 ft = 181.5HP.
The 50% more claim is based off the N/A 850 Patriot at 10000ft. That would mean a N/A Poo 850 Patriot is making 90.75HP @ 10,000ft.

50 % more of 90.75 is 136.125.
To get 90.75 to 181.5 would be 100% more

 

[o zone guy]

My math was 10% more than doos 850T (165HP) @ 8000 ft = 181.5HP.
The 50% more claim is based off the N/A 850 Patriot at 10000ft. That would mean a N/A Poo 850 Patriot is making 90.75HP @ 10,000ft.

your close but no cigar .... 118 hp at 10,000 feeT..remeber the 850 stock moTor makes 165 hp at sea leVEL
now add 12.5hp for performance pipe , now add 4hp for ( 1 ) reed valve total =12.5 +4 =16.5 +165hp =181.5 HP at sea level
now u lose 3% for every 1000 FeeT of elevation ... so 181.5 x .97 = 176 HP now dooo that 10 more times... Quick answer 129.8 HP at 10,000 feet... this includes the variables added iNN pipe 12.5 hp and ( 1 ) reed 4hp... so conclusion 850 N/A 850 stock motor @10,000 ft 118 HP .... and 850 N/A 850stock moTor with ( 2 ) bolT ons 129.8 HP aT 10,000 feeT... hope this heLPs .. HoLA !!

 

[o zone guy]

Boost increases horsepower by increasing air density, more oxygen = more fuel = more hp.

Compressing air heats it, in the case of the 850 Patriot Boost pushing 9lbs of boost at 10,000ft will add 70c-100c to the intake temps. The increase in charge air temperature reduces air density by 25-35%, so the boost pressure adds about 90% more air density, the heat from compressing that air pulls away roughly 1/3 of that.

The 850 ETEC Turbo pushing 4lbs boost at 8,000ft will add 30c-50c to the intake temps. The increase in charge air temperature reduces air density by 10-20%, so the boost pressure adds about 40% more air density, the heat from compressing that air also removes about 1/3 of that.

Adding boost is not a linear curve, it takes increasingly more boost to make more hp, particularly when intercoolers are not used, as is the case with both 850 turbos.

Moral of the story is, the best aftermarket part someone could build for these sleds is an intercooler, add with that extra boost and fuel and 200+hp comes very easy.

Gale Banks has a pretty good video on density vs hp, it's related to 4 strokes but the principles are the same, and he states why quoted boost pressure isn't a sure indication of power output.

https://www.youtube.com/watch?v=hbsnzC3nXOU&ab_channel=BanksPower

i like the way u THInK .. so we work together to break iT down into LaYmans terms for fellow snow n mudders ... i save u for lasT .. kooLbeans

 

[o zone guy]

50 % more of 90.75 is 136.125.
To get 90.75 to 181.5 would be 100% more

i like the way u think... good answer
...

 

[ABMax24]

My math was 10% more than doos 850T (165HP) @ 8000 ft = 181.5HP.
The 50% more claim is based off the N/A 850 Patriot at 10000ft. That would mean a N/A Poo 850 Patriot is making 120.67HP @ 10,000ft.

Fixed it for you

 

[Modman]

thats were the POLARIS reed valve comes in at 4 HP ... great question .. braking iT all down down .. ii Like that... BRP needs this in there inlet tube before and after the bypass valve opens and closes

Please just stop. This is not true and more related to ECU mapping and exhaust valves. They could have made that "181 HP" with a torque number of 125 ft/lbs at 7600 rpm. I've analyzed the dyno information and the Doo makes 123 ft/lbs at 7250. Run that number at 7700 and its dead nuts at 181 HP. Turbos make torque lower so why wouldn't you measure it at the lowest peak torque RPM (unless of course it suited the marketing dept to post a bigger # than the competition so you cherry picked the higher RPM).

I don't know where the fawk you guys are getting your numbers, but the Doo Turbo put down well over 175 HP last year (closer to 177-178) for peak HP at the same RPM. Why Polaris is claiming 181 HP with 9 lbs of boost I'm not sure and not sure where it was measured. 850 Matryx made 175.2 HP and 115 ft/lbs at almost 8100 RPM so I'm not sure where this all got lost in the translation. Read into it some more, probably says something like "can make up to 9 lbs" but usually runs 4-5 lbs. Kinda like fuel can contain "up to" 10% ethanol but rarely does...but yet everyone assumes its always 10%.... if you push that 115 ft/lbs to 8800 RPM you'll be making 193 HP on a stock 850 motor....at least on paper anyway.

I really wish you guys wouldn't believe all this **** in the sales brochures without understanding the numbers.....it's there to justify the $26K pricetag. let's wait til the Poo 850 turbo hits the dyno then we'll talk actual numbers. Regardless of what happens in the dyno cell, I wouldn't worry too much about the paper numbers Sean. How they perform on the hill is all that matters.

 

[firstdoo]

Completely correct. My bad. 181.5HP=121HP@50 more.

 

[o zone guy]

Fixed it for you

close small prize off the shelf .. look up and prove me wrong my friend #22 ...3 up from your peg #25 .. no worries .. i understand !! HoLa !! no war !! peacePiPE !!

 

[ABMax24]

Please just stop. This is not true and more related to ECU mapping and exhaust valves. They could have made that "181 HP" with a torque number of 125 ft/lbs at 7600 rpm. I've analyzed the dyno information and the Doo makes 123 ft/lbs at 7250. Run that number at 7700 and its dead nuts at 181 HP. Turbos make torque lower so why wouldn't you measure it at the lowest peak torque RPM (unless of course it suited the marketing dept to post a bigger # than the competition so you cherry picked the higher RPM).

I don't know where the fawk you guys are getting your numbers, but the Doo Turbo put down well over 175 HP last year (closer to 177-178) for peak HP at the same RPM. Why Polaris is claiming 181 HP with 9 lbs of boost I'm not sure and not sure where it was measured. 850 Matryx made 175.2 HP and 115 ft/lbs at almost 8100 RPM so I'm not sure where this all got lost in the translation. Read into it some more, probably says something like "can make up to 9 lbs" but usually runs 4-5 lbs. Kinda like fuel can contain "up to" 10% ethanol but rarely does...but yet everyone assumes its always 10%.... if you push that 115 ft/lbs to 8800 RPM you'll be making 193 HP on a stock 850 motor....at least on paper anyway.

I really wish you guys wouldn't believe all this **** in the sales brochures without understanding the numbers.....it's there to justify the $26K pricetag. let's wait til the Poo 850 turbo hits the dyno then we'll talk actual numbers. Regardless of what happens in the dyno cell, I wouldn't worry too much about the paper numbers Sean. How they perform on the hill is all that matters.

Only way we'll know forsure is to have both 850 turbos run back to back on the same dyno on the same day.

That being said, logic dictates that 2 different 850 motors that make the same power naturally aspirated, when put on boost, will make similar power at the same boost levels. It therefore follows that more boost makes more power, from everything we can see the Patriot makes more boost.

I'd really like to see the correction factor used on that 178hp Doo run, something sounds pretty fishy there.... Almost as if the dyno run was made at 3000ft, and a correction factor was applied to compensate for elevation, while the turbo was also adding boost to compensate for elevation....

 

[o zone guy]

Only way we'll know forsure is to have both 850 turbos run back to back on the same dyno on the same day.

That being said, logic dictates that 2 different 850 motors that make the same power naturally aspirated, when put on boost, will make similar power at the same boost levels. It therefore follows that more boost makes more power, from everything we can see the Patriot makes more boost.

I'd really like to see the correction factor used on that 178hp Doo run, something sounds pretty fishy there.... Almost as if the dyno run was made at 3000ft, and a correction factor was applied to compensate for elevation, while the turbo was also adding boost to compensate for elevation....

another small prize ... actually done at 3000 FeeT where the sled made 165 HP from 181.5 at sea LeVeL... would u like to trade your 2 small prizes for 1 medium .. peacePiPe !! thanks .. this is awesome !!

 

[Longhairfreak]

Something isn't right. At 9 lbs of boost it should be making over 200 hp.

 

[fynnigan]

Something isn't right. At 9 lbs of boost it should be making over 200 hp.

There is some truth in what you saying . Is the turbo putting out 9 lbs of boost but at a very low volume ?

 

[skegpro]

Math is hard

 

[rknight111]

aarrhhh matey i talk more about this tonight ....after dark

Thats when your typing goes crazy and your hard to understand.

 

[maxwell]

Math is hard //uploads.tapatalk-cdn.com/20210303/ebb6ce1731bd94f7ba9de9d5a091318e.jpg

We all get that, wasn’t really the question

 

[MarkCos]

Ya it is the ?

*30lb lighter than doo*
real turbo -9lb boost
185hp every where
all new sled

when u complain/pick apart.... the best sled ever built to date
ur old g4 tub is looking fat heavy long and old. So don’t point it all out -lol

 

[o zone guy]

There is some truth in what you saying . Is the turbo putting out 9 lbs of boost but at a very low volume ?

the volumetric efficiency with a bigger turboo size and smaller housing size ... thats more then 10% outside the standard turbo ratio 1.60 would create way to much LLLaaaaGGG ... think about what the turbo size would be based off of 9psi... 9 x 1.6 = 14.4 size turboo ... possible that they could run a size 16 turbo for low volume and this would be max turboo size with 9 psi 16/9 = 1.77 ratio .. but it could add up .. but it doesn't make sense when there are some better options to chose from ... this scenario is something u would see as a back yard garage experiment .. LHF would u agree... frankinsled would be proud ... polaris just trying to send u down a rabbit hole ...wankK !! wankKK !! side note BRP set the standard of 1.60 ratio size 8 turboo wit 5 psi housing 8/5 = 1.6 ratio

 

[Rene G]

There is some truth in what you saying . Is the turbo putting out 9 lbs of boost but at a very low volume ?

The 9psl is at 10000ft. It works it’s way up as tou climb in elevation.

 

[firstdoo]

Both have a lot of power (850T - 165HP ; 850BOOST - 181.5HP). Most guys that are (and are going to be) running these sleds can't even handle the 850N/A's. Kinda like me. lol. It's going to be nice in a few years when all the 'Jerry's' will be selling these sleds with low low low miles on them for non-covid prices.

 

[o zone guy]

The 9psl is at 10000ft. It works it’s way up as tou climb in elevation.

so what your saying is theres new technology ... but it hasn't been released into the market place..... yes ... back up the proof ... snow n mudders are curious ... thanks rene G... go aHead ... your up... beeP !!! beeP !!... how does it make the adjustments from 5.5 psi to 9psi to 10,000 feet rene G ???? ... i call bull****... even thou u can automatically add boost to compensate for the rise in elevation ... the turboo to housing SiZE RATIO stays the same ..yes u can put more or less psi through the turboo automatically ... but the keY going both ways is that your going to go outside the standard volumetric efficienY 1.60 and going beyond the 10% limit... u can't maintain volumetric efficiencY... so going outside the 10% on the turbo size u would have to much lag ..{ turbo/motor ( to rich ) } and going outside 10% on the housing size u would be to LeaN { housing /motor ( to lean ) }... thanks for bringing this to the surface ... this is good stuff .. much respects aLL around.. side note: once the turbo/housing is put in and your riding your sled from 0 to 10,000 ft and say your at 6000 ft... Ya can't just hit a button to change the turbo size and housing to compensate for volumetric INeffeciencY as u RiSE in elevation.. yes u can add more boost automatically but that doesn't change the other 2 variables ..remember VOLUMETRIC EFFICIENCY is TopP PrioriTy .. please read over n over ... its a complex answer ... I'm just learning ...HoLA