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Speedwerx supercharger install pics.

So Polaris new HO motor with the electronically controlled exhaust valves could this be done with the ECU?? Just have the sensor go off boost pressure

It needs to be on the far side of expansion chamber, the tuned pipe on a 2 stroke makes a 2 stroke work, with a super charger you can over pressure the intake over the pipe. On turbos you want to stay around 7 lbs max more in the pipe over the intake. This is why on a 28 series turbo they run a .82 ar but on a 3071 (on 800) you can get away with a .64 ar. But a .64 ar on a 28 series will create to much back pressure causing the opposite of a supercharger. The SC will basically blow it through and you don't get the right tune from the pipe. That's one reason why you don't see SC pushing big boost yet, or only in cases where the tuner knows his stuff. Now if you can control the pressure on both ends (I don't know for sure what's best but let's say 5lbs in pipe over intake) you could have a solid system with better economy and response, to unlimited boost.
It could be done mechanically but it could get tricky, if you used a smaller singer with tail and a 5lb spring. But then ran an intake boost line to the other side of diaphragm to equalize the pressure, so that the tail only opens when the exhaust side is 5lbs more than intake side.

Make sense.
 
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It needs to be on the far side of expansion chamber, the tuned pipe on a 2 stroke makes a 2 stroke work, with a super charger you can over pressure the intake over the pipe. On turbos you want to stay around 7 lbs max more in the pipe over the intake. This is why on a 28 series turbo they run a .82 ar but on a 3071 (on 800) you can get away with a .64 ar. But a .64 ar on a 28 series will create to much back pressure causing the opposite of a supercharger. The SC will basically blow it through and you don't get the right tune from the pipe. That's one reason why you don't see SC pushing big boost yet, or only in cases where the tuner knows his stuff. Now if you can control the pressure on both ends (I don't know for sure what's best but let's say 5lbs in pipe over intake) you could have a solid system with better economy and response, to unlimited boost.
It could be done mechanically but it could get tricky, if you used a smaller singer with tail and a 5lb spring. But then ran an intake boost line to the other side of diaphragm to equalize the pressure, so that the tail only opens when the exhaust side is 5lbs more than intake side.

Make sense.

Yeah for the most part... I never really have understood what makes a two stroke motor tick. The only thing I question is you make it sound like its not physically possible, but yet there's SC sleds out there running 300hp with basically stock motors. Your saying they just have to be tuned right?:face-icon-small-con How is the tune keeping the fuel from blowing through the pipe if the motor isn't physically capable of stopping it?
 
Yeah for the most part... I never really have understood what makes a two stroke motor tick. The only thing I question is you make it sound like its not physically possible, but yet there's SC sleds out there running 300hp with basically stock motors. Your saying they just have to be tuned right?:face-icon-small-con How is the tune keeping the fuel from blowing through the pipe if the motor isn't physically capable of stopping it?

I don't specifically know how they are making it work, I know they have but I also know some don't when turned up, so I'm very Curtis to know why? Or what they did different.
 
Yeah for the most part... I never really have understood what makes a two stroke motor tick. The only thing I question is you make it sound like its not physically possible, but yet there's SC sleds out there running 300hp with basically stock motors. Your saying they just have to be tuned right?:face-icon-small-con How is the tune keeping the fuel from blowing through the pipe if the motor isn't physically capable of stopping it?

Any dyno sheets available on that 300hp sled ? Or any supercharged 2stroke for that matter ?

I haven't found a single one.
 
Any dyno sheets available on that 300hp sled ? Or any supercharged 2stroke for that matter ?

I haven't found a single one.

I know a turbo 1000 is capable of that pretty easy but never seen it on a 800, 280hp was about the highest I know of and thats for dyno or chute pull not actually rideable power imo
 
I know a turbo 1000 is capable of that pretty easy but never seen it on a 800, 280hp was about the highest I know of and thats for dyno or chute pull not actually rideable power imo

Turbo 2strokes are tried and true. Think I've seen a Norwegian pull close to or above 300hp on a Polaris 800 turbo. For drag racing, not actual sledding :-P

I'd LOVE to see a dyno on one of those supercharged sleds tho. To see what happens when rpm and boost start climbing. Not only peak power but the power curve. Fuel flow. Torque. AFR etc.

Weird enough I can't find one. And for the kind of money the kit costs I would demand one myself. But maybe that's just me :noidea:
 
Those videos are kind of a joke.. the one is a 2011 Jackson video and the other is a cat against a bunch of poo's.. those poo's will loose on any given day with any given turbo, boost for boost.

Not sure what videos you were watching, Jackson video was last years final dash for cash... Other was this year at Xgames that had every brand there is that entered it. I think the only brand that did make the final was ski doo, there were cats, poos, and the almighty king of turbo power Yamaha in that final race. That was about as close of race anyone got to that cat at Xgames, he dominated every heat race.
 
Yeah for the most part... I never really have understood what makes a two stroke motor tick. The only thing I question is you make it sound like its not physically possible, but yet there's SC sleds out there running 300hp with basically stock motors. Your saying they just have to be tuned right?:face-icon-small-con How is the tune keeping the fuel from blowing through the pipe if the motor isn't physically capable of stopping it?

I suspect it takes different expansion chamber lengths/shapes for different boost levels to make them run right. From what I understand, a 2 stroke requires a pulse wave reflecting back to the cylinder to keep the fresh air/fuel mixture in the cylinder until the piston travels up far enough to close off the exhaust port. One pipe shape won't be optimal for the entire RPM range either. There will be one RPM that it's matched perfectly to the cylinder port timing and everywhere else is a bit of a compromise. That's why some pipes are better for low-mid power and some are soft on the bottom and scream on the top end.

With a turbo system there is additional backpressure from the exhaust having to spin the turbine wheel. The more boost you want to generate, the more pipe pressure it takes to spin the turbo. There is also a waste gate to help regulate pipe pressure too. With a supercharger you are relying entirely on having the correct pulse wave and backpressure from the stinger size/can. I'm guessing one pipe will work for 6-8psi, one for 8-10, one for 10-12, etc. (made these numbers up just for discussion sake).

Someone please correct me if I'm wrong on any of this. This is just my understanding of things.
 
Those videos are a joke, we don't race we ride where conditions change and requirements are much larger.

Dyno sheets don't really mean anything either,

On average I'm using about 150hp at elevation so 200 is more than I'll ever need, and I haven't needed any yet.
 
Ahh. And there we have it, the standard answer to the supercharged dyno question.

Whats wrong with dynos by the way ?

Nobody rides or races dynos.... Dynos can be manipulated, All kinds of variables when dynoing, No two dynos will read the same.... Nothing is wrong with a dyno if they are used for what they are made for and that is a Tuning tool.

Unless your dynoing a SC sled and Turbo sled back to back same day, same dyno, same boost, both tuned perfect for condition with a non biassed operator not sure what your gonna get out of a dyno sheet.

Even with all that the load of the dyno can favor one setup over the other. Or one setup can be tuned on the ragged edge for a quick little dyno run to get your big numbers.

Whats wrong with real world results on the snow by the way?
 
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Those videos are a joke, we don't race we ride where conditions change and requirements are much larger.

Dyno sheets don't really mean anything either,

On average I'm using about 150hp at elevation so 200 is more than I'll ever need, and I haven't needed any yet.

Huh? What are we talking about now? I thought we were talking about whether or not SC two strokes can run big boost and big power? Which I thought it was obvious those videos showed that it can be done.

Now your telling me you don't need more then 150hp, whats that have to do with the topic?

If all you'll ever need is 200hp why not run the pump gas SC that has awesome throttle response and low end grunt for your style of tree riding abilities?
 
Huh? What are we talking about now? I thought we were talking about whether or not SC two strokes can run big boost and big power? Which I thought it was obvious those videos showed that it can be done.

Now your telling me you don't need more then 150hp, whats that have to do with the topic?

If all you'll ever need is 200hp why not run the pump gas SC that has awesome throttle response and low end grunt for your style of tree riding abilities?
Because they don't work, remember. Even though we have probably over 4000 miles on a combined 6 sc cats this year. Running from 6.5-9 lbs all on pump gas, and all with extremely good results.

I don't have any video of it, but my sled is a 153 2.6 with sc at 8 lbs. Rode with a couple aero charged t3 174s at 8 lbs in Cooke. They made some very long pulls up some good chutes in goose creek. I made the same pulls just after, in my own track and made it out every where they went, with a lot more speed. My track speed is close to 60, with a next stage gauges corrected speedo. Take it for what you want, but they have worked great for us, we have sold a few more, and will he riding the same sleds next year.
 
Well what needs to happen here is both sides of this debate need to go riding together and see what happens as far as fuel consumption , power and speed on similar setups.Im on a 09 m8 with my own turbo kit i can usually go any where and would love to see the sc in action.the terrain needs to be mtns with trees ,opens and climbs in equal proportions.
 
Above goose

Because they don't work, remember. Even though we have probably over 4000 miles on a combined 6 sc cats this year. Running from 6.5-9 lbs all on pump gas, and all with extremely good results.

I don't have any video of it, but my sled is a 153 2.6 with sc at 8 lbs. Rode with a couple aero charged t3 174s at 8 lbs in Cooke. They made some very long pulls up some good chutes in goose creek. I made the same pulls just after, in my own track and made it out every where they went, with a lot more speed. My track speed is close to 60, with a next stage gauges corrected speedo. Take it for what you want, but they have worked great for us, we have sold a few more, and will he riding the same sleds next year.

Like this one?
https://www.youtube.com/watch?v=nkz7BuGGLBk
 
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