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HP numbers

The way some people "break-in" engines takes for ever, and they can even end up glazing the rings before the take a seat.

When you have a brand new engine on a dyno you can seat the rings very quick.

I buy / dyno a couple brand new crate engines (not 2 strokes) every year and put them on the dyno, run them at 1/2 load at 3500 rpm until engine temp is at 190*. Then we make full, wide open throttle pulls. They will make MAX hp in less then 6 pulls, most of the time its 3-4 pulls.


Polaris uses very hard rings that take more runs than the others to seat. Sleds aren't as prone to glazing like bikes due to the more constant and heavier loads.
 
Polaris uses very hard rings that take more runs than the others to seat. Sleds aren't as prone to glazing like bikes due to the more constant and heavier loads.

Yep,
I broke in my 16 sc in about a day.
Found some good snow and ripped it.

Full cylinder pressure to seat the rings (after warm up)
Varying the throttle some and using piles of fuel and oil.
 
Really would need 3 to 6 engines in sleds mfg'd 1 week apart ea. to really get a base line? They have to be broke in properly as per Polaris recommendations. Then what temp is the outside air they are breathing? 10 -30 deg. will make a difference I would assume unless the ECM re-calculates/Dyno computer etc. does it's job? But otherwise what does it really make on the hill at different temps/humidity etc.... I would not accept a replaced ECM from what is std. equipped and properly broke in? Would like to see what differences between engines in real world assembly/part parameters/clearances/temps etc... could create? I would bet 2% roughly? Otherwise still a nice little compact powerplant!! Mike


From repeated dyno break-in on different sleds of the same year/model, the more sophisticated EFI sleds show consistent and repeatable Hp under 2%. The ETEC is a fraction of 1%. Most variance comes from break-in method, different favorite oils, fuel quality, Ethanol content (more Ethanol = more power), fuel volatility, contaminated fuel, partially flowing injectors, anything that affects the components like road salt, bad grounds, electrical gremlins, and anything else that you can think of.
 
Is it just me or does it seem odd that a different ecm was brought in. How did someone get ahold of a ecm that went through break-in mode already? Makes me think either this is a pre-production ecm or maybe they took the first production sled and ran it on a stand for couple hundred miles, then fedex that ecm to dynotech....? Maybe u can digital wrench in and remove break-in mode but they coulda did that with original. Just speculation

Doesn’t dynotech Jim post here once and a while? Hopefully he’ll chime in
 
Is it just me or does it seem odd that a different ecm was brought in. How did someone get ahold of a ecm that went through break-in mode already? Makes me think either this is a pre-production ecm or maybe they took the first production sled and ran it on a stand for couple hundred miles, then fedex that ecm to dynotech....? Maybe u can digital wrench in and remove break-in mode but they coulda did that with original. Just speculation

Doesn’t dynotech Jim post here once and a while? Hopefully he’ll chime in

Everything was done through Digital Wrench. Polaris left him with a spare ECM with break-in mode disabled to help with early season testing. With the Amsow Shootout just months away, these numbers need to match with the next 850. There is no conspiracy.
 
We’ve dyno’d Several 800ho’s at dtr. All take 30-40 Dyno sweeps to seat rings and fuel was 3.75 hours.
The new patriot 850 toke the same 30-40 sweeps to seat rings. The fuel is 2 hours now.
Rings were seated and fuel mode was broke in too ( with an ecu supplied)
The afr on the new patriot 850 is very fat. Under fuel break in its 11.8:1. When fuel break in is done it’s 12.7:1 on average. (Still fat)
Leaned out to safe afr of 13:1 it was 173 hp.

So, you have a great motor at a fat afr (12.7:1) that gets 166-167 hp back to back that’s heat soaked. That’s 12 second runs back to back . Pretty good results at that afr. Thus the 4 year warranty
 
We’ve dyno’d Several 800ho’s at dtr. All take 30-40 Dyno sweeps to seat rings and fuel was 3.75 hours.
The new patriot 850 toke the same 30-40 sweeps to seat rings. The fuel is 2 hours now.
Rings were seated and fuel mode was broke in too ( with an ecu supplied)
The afr on the new patriot 850 is very fat. Under fuel break in its 11.8:1. When fuel break in is done it’s 12.7:1 on average. (Still fat)
Leaned out to safe afr of 13:1 it was 173 hp.

So, you have a great motor at a fat afr (12.7:1) that gets 166-167 hp back to back that’s heat soaked. That’s 12 second runs back to back . Pretty good results at that afr. Thus the 4 year warranty

So did you use a controller to lean the motor out to get 13.1-1
 
So the Polaris 850 horsepower curve doesn't look like a spike at the top.
 
I look at it this way.

The highest a 850 etec got at dtr was 174 hp and that was with a y pipe, pipe,12% ethanol fuel , timing and A/F at 13.2:1.

The patriot 850 did 173 hp with just timing and A/F at 13:1 with no pipe or y pipe yet. Add a pipe with a fuel controller when they come out and it’s ahead of the doo 850 hp wise
 
so perhaps we can run a pipe without a controller just like the 800.:juggle:


I was thinking same thing only maybe there is no room for a more free flowing pipe as I expect the 850 is going to have a bigger pipe than the 800 already??
 
Disclaimer, I know nothing about who found these numbers, stolen from another forum.

New results at dynotech this year already
New Polaris Patriot 850 174.2 hp
Ski doo Rotax E-Tech 850 168.7 hp
Polaris Liberty 800HO 155.7 hp
Arctic Cat C-tech2 800 152.4 hp

Wasnt stolen from skidoo site im sure:
 
The Axys HP numbers are definitely impressive! Then, given how efficiently it gets that Power to the snow, this 850 is head and shoulders ABOVE the competition . . . .still!

Going to be a GREAT season!!
 
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