I feel dirty but I rode a Polaris boost matryx

oler1234

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“Regulate pressure in a tuned pipe”

Seriously do you even know what you guys are talking about? A ‘wastegate’ is just what the name implies, it wastes exhaust gases, in other words it’s a bypass valve for exhaust flow to regulate boost pressure.

A wastegate does not regulate pressure in your tuned pipe….

People really need to check there rpm’s on these machines, you will clearly see how inefficient the polaris clutching is, anyone with any know how can clearly hear it in the videos being posted.
 

SUMMIT TREE

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“Regulate pressure in a tuned pipe”

Seriously do you even know what you guys are talking about? A ‘wastegate’ is just what the name implies, it wastes exhaust gases, in other words it’s a bypass valve for exhaust flow to regulate boost pressure.

A wastegate does not regulate pressure in your tuned pipe….

People really need to check there rpm’s on these machines, you will clearly see how inefficient the polaris clutching is, anyone with any know how can clearly hear it in the videos being posted.
Watch that video posted where that guy from VOHK is describing the boost. Polaris is using some new fan dangled wizardry to “regulate pipe pressure”.
And to answer your question, yes. I have extensive knowledge in how a waste gate functions.
 

SUMMIT TREE

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It may not be the waste gate controlling pipe pressure, but they are doing it somehow, and maybe that dumping action is making some of these weird noises out of the exhaust?? I dunno.
 

mountianguy

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“Regulate pressure in a tuned pipe”

Seriously do you even know what you guys are talking about? A ‘wastegate’ is just what the name implies, it wastes exhaust gases, in other words it’s a bypass valve for exhaust flow to regulate boost pressure.

A wastegate does not regulate pressure in your tuned pipe…. It does on the Polaris Boost

People really need to check there rpm’s on these machines, you will clearly see how inefficient the polaris clutching is, anyone with any know how can clearly hear it in the videos being posted.
Polaris has the turbo at the end of the tune pipe mounted on the muffler. They also use a second path for the exhaust to escape pre turbo. It is on the pre turbo exhaust path where the wastegate lives. It is controlling pipe pressure that is feeding the turbo. There is more than one way to turbo a 2s apparently.
 

NoBrakes!

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Smartboost... another word to add to the 9 word name

Oler, take it easy bud.


1640791595620.jpeg


twin core muffler, twin exit....
 
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ABMax24

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You guys are arguing over marketing language.

All turbos regulate drive pressure ("pressure in the tuned pipe") to control how fast the turbo spins and in turn how much boost is produced. Turbo RPM is a function of drive pressure, period. Garrett turbos have been the norm for many aftermarket turbo kits, they have an integrated wastegate built into the turbine housing that is operated by an actuator driven by boost pressure, when the desired boost pressure is reached the wastegate opens to control boost pressure. Some kits have used non-wastegated housings where an external wastegate has been used, the Tial wastegate was in use at one point, but the function is the same.

The difference with the Polaris Boost is the wastegate is being controlled electronically by the ECU, driven by an electronic actuator identical to the one controlling the power valves. There are advantages to this, such as opening the wastegate under part throttle to limit exhaust back pressure and lower turbo rpm when boost simply isn't needed. If an exhaust back pressure sensor was placed in the exhaust it could also be used to limit backpressure and prevent cracking the pipe and undesirable drivability characteristics associated with excessive backpressure on a 2-stroke engine.

In those videos there is a definite surge out of the exhaust, could it be the rev limiter from poor clutching, maybe, but I have a bit of a hard time believing Polaris would give Brett Turcotte a sled to demo for the day without installing the correct clutch weights first. It could be caused by the ECU regulating boost or backpressure, but as I've already stated this is a poor way to do it, at WOT the wastegate should find its sweet spot and stay there, it shouldn't be cycling causing that flutter out the exhaust.
 

Clode

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Sounds like over-rev to me, throw some weight at it or gear it up to load the engine.
 

adamg

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Gear it up
Does a Boost 165x2.75 come with the same gearing as a NA 165x2.75? Because if it does, that might be a problem. They finally geared their belt drive sleds way down this year with the QD2, which is excellent for NA power. But for turbo, it might be too short of a gear, maybe they should switch to QD1 parts for the taller drive ratio.
 

Caper11

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Lots of misinformation in this thread. Anyway, I think the guys that ordered any factory turbo are going to like them alot, regardless of the sounds they make or how they make boost.

The excess boost pressure has to go somewhere, the sleds do not have blowoff valves. The doo blows the excess out the air box, and the Polaris dumps it out the exhaust disrupting the exhaust tone, and sound.

The boost sounds like a tunnel dump aftermarket muffler.
 

mikermz250

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You guys are arguing over marketing language.

All turbos regulate drive pressure ("pressure in the tuned pipe") to control how fast the turbo spins and in turn how much boost is produced. Turbo RPM is a function of drive pressure, period. Garrett turbos have been the norm for many aftermarket turbo kits, they have an integrated wastegate built into the turbine housing that is operated by an actuator driven by boost pressure, when the desired boost pressure is reached the wastegate opens to control boost pressure. Some kits have used non-wastegated housings where an external wastegate has been used, the Tial wastegate was in use at one point, but the function is the same.

The difference with the Polaris Boost is the wastegate is being controlled electronically by the ECU, driven by an electronic actuator identical to the one controlling the power valves. There are advantages to this, such as opening the wastegate under part throttle to limit exhaust back pressure and lower turbo rpm when boost simply isn't needed. If an exhaust back pressure sensor was placed in the exhaust it could also be used to limit backpressure and prevent cracking the pipe and undesirable drivability characteristics associated with excessive backpressure on a 2-stroke engine.

In those videos there is a definite surge out of the exhaust, could it be the rev limiter from poor clutching, maybe, but I have a bit of a hard time believing Polaris would give Brett Turcotte a sled to demo for the day without installing the correct clutch weights first. It could be caused by the ECU regulating boost or backpressure, but as I've already stated this is a poor way to do it, at WOT the wastegate should find its sweet spot and stay there, it shouldn't be cycling causing that flutter out the exhaust.

Looks like maybe they did send him a sled not clutched properly…
 

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greenthumb

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Buddy is on his way out west from the east in a few days. Supposed to be here already, but has no sled; waiting on his new poo. I'm still waiting on my t-doo, but hopefully soon. Neither of us work in the winter and the plan is to ride as much as possible until mid-feb. We are pretty equal skill, so should be a good comparison. :p
 
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jhurkot

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There’s an extra Khaos 155 boost at E&s Motorsports. Call and ask for Samantha.
 

OOC ZigZag

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Nice machine it runs nice and clean on and off boost. Good throttle response. Sled ran consistent all day. But I was expecting a little more out of it. When Polaris said they had a 180hp machine that’s lighter I really thought skidoo camp was in trouble. Back to back pulls against a 2022 165 turbo skidoo they were pulling identical track speeds in multiple repeated attempts. Deep snow. 70kmh for the factory 2022 skidoo and 42mph consistent for the Polaris. Being 180 claimed HP spinning a narrower track with less lug height i was really expecting numbers in the mid 50mph. These speeds I’m posting are fully loaded deep snow before turnout. Not some of the numbers you fellas post rocketing up a hard pack hill it’s the real deal as loaded as a sled can get. Either skidoo is lying about it’s 165 HP or Polaris is lying about 180. OR Polaris drivetrain is having issues getting that power to the ground. Both machines are strong but the skidoo turbo is still a cleaner running more refined package. It also pulls a lot harder in the mid range and much less lag on the bottom end. There was no skidoo turbo inialation today I’ll tell you that for free. I’m not knocking the sled at all. It’s works well and is night and day faster than an NA 850 and glad to see the industry moving forward. But all this talk of blowing skidoo’s out of the water just isn’t going to happen. I think once the clutching and gearing wizards start tinkering we might be in trouble but stock to stock the skidoo turbo and Polaris turbo perform very similar. Everyone will be happy with them. It’s nice when my Polaris friends are right behind me now. It’s been lonely at the top the last 2 years.
Now let’s see how they handle the test of time. My bet Poo’s gonna win most time at the end of a long line.
 
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