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I think 9 would be fine for 17.5 psi
I was also understanding that if the hurricane ecu was installed, you’d have over 20 psi , don’t think they adjusted the crack pressure.
i also tried the Mach clutching on a 19 205 hurricane renegade x and works perfectly
im also seeing higher rpm’s on the Mach in standard mode
I honestly think the lower rpm has something to do with the launch control and the helix.
I do honestly think the ecu is limiting timing or boost , my Mach runs higher rpm’s at lower water temperatures
what does your guys sled run for temp, mines around 165 to 170 pretty much all the time , but if I try it at 100 I appears stronger.
dyno sheet also has a lower water temp
With the hurricane ECU installed I get just under 22PSI of boost. This is with no adjustments to the stock wastegate.
 

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Yes, worthwhile to see if octane boost makes a change. My guess is that octane is not likely to enter into this matter: Adding octane does not add power, only detonation resistance. Having said that, a given higher octane fuel may run better with more power, but that is usually due to a different additive mix, like less ethanol, not the octane rating. The ECU has no way to measure octane... it only reflects in detonation.

One major design goal here in a production sled is to avoid detonation. This is not a diesel with the heavy internal construction... detonation is any everyday thing in diesel-land. You can be sure they kept a lot of margin in the programming to detonation. Can anyone cite that source of the 17.4 psi max boost? I'd like to see the context; that may have been early promotion and the reality crept in later to force a lower limit.

And yes engine temps enter into the programming action. IDK what they may be doing with engine temps here other than the obvious warm-up enrichment, and controls for overtemp situations. The main temp used is the IAT (inlet air temp) which is used to approximate air density.
See post 230 for where the 17.4 came from
 

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Yes agree....was first thing I fixed after first couple runs, was VERY loose from factory.

For those that are not sure why, the deflection is mostly felt on "drive-off". When the belt has too much deflection or LOOSE, this put the belt higher into the primary on drive-off, so in essence you are in a higher gear. What many dont understand it, that once you are riding the springs take over. So once you let off and get back on the throttle, the belt will then be tensioned only by spring pressure.

So a loose deflection can hurt bigtime on a drag race for instance, as the belt will remain in that higher gear until you let off throttle. In the end it does seem to always gain a small amt of RPM on top, but helps moreso with drive-off.

Take into account with mechanical reverse the actuator can get hung up and cause an error.

Dan
So loose deflection so it still goes in reverse not enough power so need more boost to pull the stock clutching thanks skidoo
 

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When i pick up my mach this week i am installing this boost guage and will have my eyes glued to it since there is no way to datalog any useful info.
Im not touching any clutching until i am convinced this engine is boosting and running 100% View attachment 1987007
Is it the Koso X-1 ?

Let me know where you put the boost sensor on the 900R. If you can take a picture, it would be appreciated.

Envoyé de mon SM-G960W en utilisant Tapatalk
 

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Is it the Koso X-1 ?

Let me know where you put the boost sensor on the 900R. If you can take a picture, it would be appreciated.

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Yes it is and can do..
 

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I put a PB80 on mine and am getting the RPM's in the 7900 - 8000 range but this thing still doesn't top end. Dreammeter shows max110 mph and I've got about 550 miles on it.....I would have expected at least 115 on this thing. Love the sled but it underperforms on top end......Ski Doo screwed this up, lots of hype, big downer!
 

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ECU closing the throttle. Tq management. 1200 throttle by wire used to do it. Couldn’t see it except watching on dyno. Ecu rolls tb closed from
100% to say 80%
Dang.....there's something I had not thought about.... So now maybe we have the throttle roll out from the ECU. One more thing to throw on the pile.

The fact that it takes this action would not by itself cause the variations in max RPM. Variations would be the variation in what the ECU 'sees' as RPM, and the programmed 'softness' in the control response vs. TB motor response.
 

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Fantastic... thanks a ton!

First clue spotted... air flow stalls at around 7600 RPM. Look over at the boost column.... boost starts cutting back. If the engine was choking to cause the airflow stall, then the boost would not drop.

So it could well be that the electronic boost controller is being used to throttle back boost above a given RPM. Seems likely, though this does not 100% rule out the turbo compressor running out of poop at a given engine RPM.

The electronic boost control and waste gate action are not precision devices... not even close . And the control programming is a 'soft cut' so as to not make the limiting action a violent occurence. These 2 together, along with the MAP sensor variations, could explain the RPM variations entirely.

(As a side observation: Since this is probably run on a dyno where the RPM is ramped up in a 'run', rather than taking steady state readings at individual RPM's, that may explain the low boost at lower RPM's. The turbo may still be spooling up as RPM's climb. No way to know for sure from this type of dyno 'run'.)
 

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Dang.....there's something I had not thought about.... So now maybe we have the throttle roll out from the ECU. One more thing to throw on the pile.

The fact that it takes this action would not by itself cause the variations in max RPM. Variations would be the variation in what the ECU 'sees' as RPM, and the programmed 'softness' in the control response vs. TB motor response.
BRP uses the the throttle plate to limit peak output and you wouldn't even know it. Something you don't see even when fully connected to the ecu via tuning software.
 

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OCD Sledhead
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Discussion Starter · #252 · (Edited)
Finally getting caught up here after much testing all weekend.

First off, lets just back up a bit as to this particular thread's OP. While I understand threads take on a life of their own and it's good to move onto other theories, let me just begin with what i was attempting to figure out in the OP.

Clutching Issues:
I had a Mach revving 7400-7500 right next to an Adrenalin revving 7900-8000. Both brand new sleds of 2022 model year. So the clutch component swap was on, and first proved the ADR ramps would make the Mach rev the same. First question was answered and concluded the Mach did have same power as the Adr.

Hated the Mach ramps, got the Daltons very fast from Chris and slapped them in. Set them up initially from the testing experience at 2.7g to center of body(bottomed) with tip open @77.6g total. This worked quite nicely, and had the Mach revving 8200 cold, and 8000 warm with a long haul fall back to a solid 7900 hot lap.

The big test came Sunday with our big local lake being ready to get onto ice(Lake of Bays).... side by side with Dano's test mule Adrenalin bone stock. Just to refresh memories, the Adrenalin initially had 5mph and 500 rpm over the Mach. Now with the Dalton adj ramps, these two sleds were basically identical in speed. Tapped 112 & 113GPS in some sections of the lake which has less snow than others.

So this was my goal of this thread, to answer the question why my Mach was so far off from the Adrenaline. I do think the 880 ramps are much nicer then the Mach ramps overall, however I love the Daltons for their obvious adjustability as I can dial in rpms for diff belts ect ect.

For me this is how you clutch, start with ramps with a range, now I will move to the springs of my choice(Dalton brand) that will not sack over time, I do this on all sleds I own, not just this Mach. I also believe we need less helix angle, and will be ordering that as well.

Other issues:

After a long day of lake running and watching the tach, I have some conclusions.

First off, i do not feel there is any octane(or lack of octane) ECU intrusion. We tried alot of short and very very long pulls holding WOT for 3-4 miles even, and my RPMS held solid. Longer hauls would stick at 7900 once all was hot. Never below.

When hitting snow/ice sections the Rpms drop a fair bit though, then come back fast.....this is telltale sign of too soft back-pressure or in other words secondary spring not holding solid rpms. Secondary is reacting to the surface change from ice to snow. My answer will be more spring and less helix combo. Always been a big fan of Dalton helix too, Dale works his magic on the design and top quality bushings, all measured in equal manner as BRP helix. 47 is far too steep for start, and 40 is too steep for finish. I will certainly post what I end up with after testing down the road. Also will be adding more primary spring as well, along with Ultimax.

In the end, this ECU is not producing anywhere near 17.6PSI IMO. It certainly feels strong in middle but top end just doesnt have it. I would be surprised if this was anywhere over 14psi peak boost.

I really dont think this will change either. The more miles I get on this sled, the more I think there is NO break-in 'chip' at all. It's been running exact same since day 1. I have close to 300 miles now on ticker and have gone through well over 3 tankfuls with no change in power.

I do not think there are any boost leaks as I have checked every connection, and I do not think that there is any crack pressure issue being too low ect.

Unless the ECU magically unleashes more boost at 1000 miles or something, i think BRP will need to come out with a reflash or something. For them to advertise 17.6PSI last fall and suck us all in, and deliver 14-15psi or so is really terrible.

And Nick has been testing the standalone from Hurricane with great success over 20psi or so, and crack pressure hold fine, and i think his forearms are sore from holding on! So these engines as designed can run strong, its the ECU holding us back and likely BRP can fix that but will they???

Dan
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Be curious to see if you up the crack pressure and boost stays the same or goes up. If it stays the same you know it is something in the programming
Spot on. Could still be some minor variations of boost vs RPM with varying crack pressure, but the trend of boost dropping past a certain RPM ought to remain if it is the ECU programming.
 

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rockerdan, is your testing with a stock 571 belt or are you running the ultimax already? Reason I'm asking is, I have Dalton's in my Renegade X with silver screw in the tip and 3.4g toward the heel and I'm at 8-8200 with all other clutch components stock.
 

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OCD Sledhead
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Discussion Starter · #255 ·
rockerdan, is your testing with a stock 571 belt or are you running the ultimax already? Reason I'm asking is, I have Dalton's in my Renegade X with silver screw in the tip and 3.4g toward the heel and I'm at 8-8200 with all other clutch components stock.
Yes stock 571 belt. I am switching over to my Ultimax though moving forward.

One thing missing from my kit is that silver tip screw(used kit) and if I had it I wanted to load that. The steel tip screws were too much for mine. I would leave that in there if you are at 8000 solid HOT laps.

Remember the Heel slug when loaded at extreme heel will do very little toward top RPMS but will hit harder in bottom and mid. I tested my heel fully loaded with an additional 2.1g flush to heel and it did go to top MPH much faster i felt. However with that much overall body weight it lost its quick rev ability. So Im aiming for somewhere in between.

The beauty of these ramps are the huge range of ways you can set them up, to anyones liking for any style, one setup for tight trails vs another setup for lakes....love them.

Dan
 

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To the guys running the boost a gauges pick up a manual boost adjuster and put it in place of the stock on see if you can make the sled run the 17 psi.

my guess for tree guy will have one kicking around to try

in theory your max boost is crack pressure doubled when using a boost controller
 

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Yes stock 571 belt. I am switching over to my Ultimax though moving forward.

One thing missing from my kit is that silver tip screw(used kit) and if I had it I wanted to load that. The steel tip screws were too much for mine. I would leave that in there if you are at 8000 solid HOT laps.

Remember the Heel slug when loaded at extreme heel will do very little toward top RPMS but will hit harder in bottom and mid. I tested my heel fully loaded with an additional 2.1g flush to heel and it did go to top MPH much faster i felt. However with that much overall body weight it lost its quick rev ability. So Im aiming for somewhere in between.

The beauty of these ramps are the huge range of ways you can set them up, to anyones liking for any style, one setup for tight trails vs another setup for lakes....love them.

Dan
For sure. I couldn't get the slug in any farther with the little allen provided so I just left the weight in the heel to see what happened. I do feel that once I added the weight, it pulled better in the middle, but still lost a few MPH on top. Again, it was turning 8,200 at first, then would lay on 8,000 on the way back from our ride. I now have roughly 640 miles on and I haven't noticed any difference in power.
 

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Yes stock 571 belt. I am switching over to my Ultimax though moving forward.

One thing missing from my kit is that silver tip screw(used kit) and if I had it I wanted to load that. The steel tip screws were too much for mine. I would leave that in there if you are at 8000 solid HOT laps.

Remember the Heel slug when loaded at extreme heel will do very little toward top RPMS but will hit harder in bottom and mid. I tested my heel fully loaded with an additional 2.1g flush to heel and it did go to top MPH much faster i felt. However with that much overall body weight it lost its quick rev ability. So Im aiming for somewhere in between.

The beauty of these ramps are the huge range of ways you can set them up, to anyones liking for any style, one setup for tight trails vs another setup for lakes....love them.

Dan
Let me know when you are all settled in with my next clutching setup! Lol

Other than the RPM thing, how do you like the sled? Smart shox?

I don't have a lot of miles on mine yet but it feels like I will be in sport+ mostly with a little sport mode sprinkled in. Which surprised me. I thought I would be more toward sport and comfort. I didn't realize I liked my suspension so stiff personally. Comfort is like a 1970's couch. Fine for the guys going slow but at the cost of performance.
 

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The extra 30 hp on these sleds doesn’t equal top end for some reason. The extra hp gets more low end and midrange smack but up top in any snow it’s a dog. Gears are a waste unless your riding plowed ice road. Guys will spend lots of time finding a few mph but in the end it’s still a pooch on top.


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History repeats itself again and again the machz is a let down it was always the sled at the back of the pack ever since it came out in the 90's
 

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History repeats itself again and again the machz is a let down it was always the sled at the back of the pack ever since it came out in the 90's
Thanks for your contributions coot. I'm sure your 16 posts here have been nothing but valuable.
 
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