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So What The He11 Does Work.... Build

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Boyko

Well-known member
Nov 27, 2007
771
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Alberta
You have a good ear lol, the 2860 does spool a lot faster, boost thresholds are not that far apart though. We tried to keep everything the same, clutching, same hex files in the Dobeck boxes, ect. the 82mm seems to pull a little more rpm and needs more fuel. It is hard to compare top end performance with the snow we got for now. 2 feet of powder on a long hill would be sweet.
 
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Boyko

Well-known member
Nov 27, 2007
771
260
63
Alberta
I was in BC last week, it was great.


This happened on one of the first shake downs a month ago

Any one want to guess what happened :face-icon-small-con

IMG_1268.jpg
 
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Boyko

Well-known member
Nov 27, 2007
771
260
63
Alberta
So I handed my buddy a blow off valve that the little exhaust horn was not tighten up on. Well it fell off
and rolled around in his sleds belly for a bit. He was jumping some drifts one day and his belt must have snagged
it and launched it into his Throttle Position Sensor with extreme velocity.

IMG_1268.jpg
 
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Boyko

Well-known member
Nov 27, 2007
771
260
63
Alberta
Well as much as I like how the cheap 82mm turbo is working it is time to Press On. The spool up on this big cow of a turbo is not aggressive,
the power is smooth, nice and linear but not the punch in the face that most of us look for. I have gone to like the pos 82mm, it’s kind of
tough to peel it off the sled.

To me the kPa concept represents good technology at a fair price so that is what we are tiring next. You will be seeing a lot of these turbos
next year on kits, as upgrades and replacements. I just have to get my a$$ in gear and get it swapped out


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Boyko

Well-known member
Nov 27, 2007
771
260
63
Alberta
The 63mm kPa so far rocks! Spool up is way faster, It is my experience that adding water to air set up does slow the rate boost ramps up but with this turbo it is not a concern. This is a well balanced turbo for the 800 two stroke. The advancements of real ceramic bearings and a billet compressor wheel that has a larger surface area this turbo definitely supercedes the Garrett 2871. This thing sound like a jet taking off even at low boost the turbo wine is quite audible because of the design of the compressor wheel. For me to get a Garrett 63mm billet shipped out would be almost twice as much.

Kpa does have a stainless V-band turbine housing and a 73mm billet compressor turbo available

I get some videos posted soon of my boost gauge going through the motions



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Boyko

Well-known member
Nov 27, 2007
771
260
63
Alberta
Thanks Blown Motor,the polaris you built this year looks frickin wild nice work.

Adrian I had to build the uni flange on the exhaust side of the turbo, figured I would want to try a different turbo later on
 
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Boyko

Well-known member
Nov 27, 2007
771
260
63
Alberta
Conclusion:

It is still confusing as to what works for a turbo because the cheep 82mm turbo worked better than we ever would have suspected. The boost threshold was close to a 60 mm Garrett but it wouldn't move the boost gauge as fast as the 60mm. Top end was great on the big wheel turbo as well.

Turbo sizing and designee is a significant factor for response but I do not think there is a magic bullet out there in the turbo market place. You don't have to spend big to get a good working turbo. There will be more oil less options out in the next season as well. What gets overlooked a lot is tuning. I think before anyone lays down the cash for a turbo upgrade, looking the best new thing in the turbo market they should spend some time tuning there clutching and looking at efi options. One guy in our group has a slp stage 3 on his pro and the 2 turboed RMKs are a lot snapper off the bottom end, its clutching and the way the fueling is set up. James also agrees that his sled is more snappy with the turbo on it.

The one thing that stands out the most between the two builds is the difference a water to air intercooler makes. I was running 7 psi all season James was stuck at 9psi. Everyone in are group agrees that the intercooled sled kicked on the other build pretty hard. I do not run high boost on 2-strokes, I also have never changed out a set of reeds probably because I don't rack up much more than a 1000 miles on them.

Running a large intercooler core is as important as having enough heat exchanger with a water to air. If you think your going to make 230 hp get a core that is good for at least 350hp, even bigger if it is a barrel style cooler.

This has been fun build for me, I like to thank everyone that has helped me out. It’s funny how there is smack talk about the turbo and efi suppliers for this industry, everyone of them that I have dealt with over the last +10 years have been great.
 
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NM

Well-known member
Jan 3, 2003
1,195
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Ponoka AB.
This is a great read. I know you have more turbo experience than most and I obviously agree that a water to air is critical to consistent tuning and sustainable horsepower and torque.
If money was not important, what would be your turbo of choice?
We are kicking around the idea of trying some BW EFR turbos since we use electronic boost control on pretty much everything now.
 
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Boyko

Well-known member
Nov 27, 2007
771
260
63
Alberta
Hi Neil,
and thanks

I have a EFR on my nytro, I really like it, it's the most advanced turbo out there right now. The 6358 or 6758 .64 would be the choices for a 2-smoker, the 58mm turbine in a .64 housing should keep the balance for back pressure. Looking at there maps there aerodynamics is set up for higher boost as most billet compressor wheels are. The turbo is also 1.5" longer so it would have to be orientated differently than what I did on my polaris. EFR is a great choice but I would like to go oil less next, I will wait until there are more tested choices out there for a greaser turbo.
 
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tdbaugha

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Lifetime Membership
Apr 18, 2009
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Kalispell, MT
We are kicking around the idea of trying some BW EFR turbos since we use electronic boost control on pretty much everything now.

That would be pretty neat. I wish they would make an oilless version...
 
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