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Auto Tune on the Power Commander 5 (PC-V)

E
Jan 18, 2008
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St. Paul, AB
Kraven,
You rebutted my comment about the ethanol wires not affecting timing, you are right and wrong at the same time, the ethanol wires do not switch timing on their own, they add fuel which allows the ecu to adjust timing because of less chance of detonation, altered pipe center section temps and differing throttle position input from the rider since there is a difference in power delivery due to added fuel.
 
E
Jan 18, 2008
503
96
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St. Paul, AB
First off I fully believe in the power commander setup and its obvious tuning capabilities.
There is an inherrant problem with the autotune, its like cruise control for air/fuel ratios, in saying that does anyone here drive down the road on cruise control without watching what they are doing, other vehicles, animals on the road, icy conditions etc etc.
By letting the autotune only monitor air/fuel you are not alowing the ecu to protect the motor. If all it is interested in is air/fuel, it will fight the ECU when its trying to protect the motor, the ECU richens the mixture then the autotune leans it to maintain a specified a/f mixture. So say you get detonation due to bad fuel, the deto sensor and pipe temp sensor monitor this, the ecu decides to add fuel/back off timing to cool the combustion chamber all the while the autotune is fighting to maintain its holy grail A/F, and you have a blown engine. Add to that the fact that anyone in the automotive world knows about O2 sensors and how much they like oil or anything else on them and god forbid you run leaded fuel which kills their accuracy over time as well because anything in the path of the exhaust gets a small coating of lead.

The bottom line is buy the autotune/PCV combo, it works well, and go like this:
1) do your mods
2) upload dynotechs closest map for what you have
3)richen those numbers for safety
4)ensure you have good quality fuel from the same place you always buy
5)go for a ride
6)once you have verrified that the ECU is ok with your mods (no deto, CELs) activate the autotune
7)Ride around without doing long pulls to allow the autotune to start building a map, get progressively more aggressive and make sure you cover all your riding types, full pulls, 6500RPM powder floating, 8000 down the trail under little load, basically let it see how you ride.
8)monitor everything you can, piston wash, oil consumption, coolant temps, EGTs, remember the autotune doesn't even care if you are overheating.
9) once you feel that your sled runs as you would like it to save your map and de-activate the autotune.
10) Pull your expensive O2 sensor and replace it with a plug, check all the PCV connections. Ride it, make sure everything is good to go, then enjoy your mods. Now the ECU is protecting your unwarrantied ($3000) motor and not having to fight your $300 autotune. Then let your buddies use your autotune for $50 a shot, let it pay for itself.

As for anyone worried about your voltage regulator take a few minutes and check your tailight wiring harness, it likes to short out on the tunnel taking out multiple VRs over time, finally killing the ECU due to undervoltage. Another area that I have seen is at the handwarmers, if you happen to twist your brake or throttle or added a left hand throttle or rolled the sled, just check over the wiring especially where it joins on to the warmer itself. Polaris wiring and electrical are pretty lackluster but mainly in routing and wire selection. The VR is not the problem, its just what happens to get taken out by the problem.
 
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AndrettiDog

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Dec 23, 2007
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Good info and theory ElecroTech (I say theory because at the end of the day you never know what you are getting here! ;) )

The PCV has done wonders for my sled an I'm happy. However, I can never be happy so I plan on graduating to the auto tune phase next. I don't plan on using it full time, but doing what you have stated. Make some big runs on test days and plug the hole for full time riding. I'm thinking about using EGT's to help me monitor my map changes. That will help me from burning down my motor when I lean out for more HP. Sounds good on paper anyway. A few questions to ponder...

-What will the bung do for performance? We spend money on porting to improve performance, so won't the bung (with its concave opening) affect performance while it is capped?

-Are EGT's the right tool to monitor potential burn-downs/detonation for tinkering with the map to lean down for more HP? Specifically, I want to make a short run map that I can swith to for short climbs and drag runs.

Good topic.
 
E
Jan 18, 2008
503
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St. Paul, AB
The bung gets welded to the outside of the pipe, and the plug should sit nearly flush, but I do not feel there will be any real measureable effect with the sensor in or out. With the sensor in would be the larger effect as it protrudes into the expansion chamber. We've run egts right near the ports for years and saw no ill effects.
 

thefullmonte

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Nov 26, 2007
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The bung gets welded to the outside of the pipe, and the plug should sit nearly flush, but I do not feel there will be any real measureable effect with the sensor in or out. With the sensor in would be the larger effect as it protrudes into the expansion chamber. We've run egts right near the ports for years and saw no ill effects.

I was planning on placing mine after the expansion chamber before the silencer where the pipe is straight. Do you think that would function OK? And reading the instructions I was getting the feeling you should put it as vertical as room allows. Does that seem right to you? Sounds like you have been down this road a couple times and I'm sure we all would appreciate the advice. :beer;
 
E
Jan 18, 2008
503
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St. Paul, AB
I would install it in the center of the expansion chamber where it will see the best cross section of readings and also not affect stinger diameter at all. As we know from our fancy little letter from polaris back pressure is one of our many enemies on this sled(besides polaris and the EPA).
Just for se-assurance I called dynojet and they said the same thing. Also this is where there is less chance of contamination from raw fuel and oil, just by having a larger area for those droplets to occupy, whereas in the stinger everything is funelled through.
 
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Kraven

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Apr 11, 2009
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Kraven,
You rebutted my comment about the ethanol wires not affecting timing, you are right and wrong at the same time, the ethanol wires do not switch timing on their own, they add fuel which allows the ecu to adjust timing because of less chance of detonation, altered pipe center section temps and differing throttle position input from the rider since there is a difference in power delivery due to added fuel.


I didn't know someone was keeping score.

I thought the purpose of this site was to share information so as to benefit everyone,

Not to try to prove someone wrong with theories.
 
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Kraven

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autotune, closed loop and o2 sensor.

A lot of negativity.

It seems everybody is getting overly concerned about the 02 sensor failing, now that me personally, if I had to replace the o2 sensor every season, it's not a big deal, considering the cost of snowmobiling overall.

Consider this;
1) Since 2006 the FST/WEBER runs a closed loop system that monitors and adjusts fuel and timing constantly, and it's ON all the time. (Yeah, 4-stroke I know)

2) MOTEC, an Australian company builds a $3100 HI-ZOOT version of the Autotune that adjusts fuel, timing, and even sharpens the carbides while you drive, (and its ON all the time) and is distributed by Nils, the RUDE Supercharger guy in California, his brother is on this site and has that MOTEC unit on his snowmobile. It's currently popular on the YAMAHA Supercharged Jet Skis. Yeah 4-stroke again, I know.

3) Just a few short years ago, there was no WIDE band 02 sensor readily and practically available. How long do you guys think it will be before the "next generation" BOSCH 02 sensor comes out that lasts longer under 2-stroke oil conditions?

In the meantime, if I have to toss a couple of O-2 sensors out in a season, I can live with that, I.M.O. (If you buy them at the Auto parts stores, they come with a 1 year warranty)

Enough of the negative theories, any positive comments??
 
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AndrettiDog

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Dec 23, 2007
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Any positive comments??

Ok, I'll change the momentum. Anyone have any auto tune maps they want to share yet? I'm interested in what changes and where. I know that we can't all share maps because of all the variables, but I'd like to see what is happening for different applications.
 

Rick!

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Ok, I'll change the momentum. Anyone have any auto tune maps they want to share yet? I'm interested in what changes and where. I know that we can't all share maps because of all the variables, but I'd like to see what is happening for different applications.

In general, the auto tune will richen up a diagonal from, say, 4500rpm/5% TPS to 6750rpm/40% TPS which may or may not fix some driveability issues on CFI 4 injector twins. In my case, it deteriorates the injector switchover thingy. So, a guy would then revise the target AFR map and retune or just cut out some of that map to minimize tuning "distractions". Autotune works really well for top end "jetting". Enable it, run hard for 30-40 minutes and use the 80%-100% TPS values for 7500rpm and above and you should be jetted for the day. (check and record density altitude for background info and map naming conventions.) You could do all this while the rest of your buddies are still in the hotel or driving to the snow park.

Advanced stuff is playing with individual injector maps but that is beyond most PC V user's involvement level.

Since you can actually generate different maps for different clutching, it would be optimistic to get a low elevation generated map to work at altitude and vice versa. There is one map that comes with an aftermarket pipe mfr that incorporates some cool things and seems to work. I'll know more after this weekend.

Oh, autotuning at -15F and 84% humidity makes frosty everything and can actually add fuel at 100% TPS.

Visual inspection of my O2 shows nothing unusual after 600 miles and I don't notice any degredation of displayed AF ratios.
 

dragonfire

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Dec 2, 2007
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Fargo,N.D.
Aototune capabilities

Electrotech and Mountainhorse thank you for the good posts on this subject as I share the same enthusiasm about this product and also have the same reservations about its capability. I would like to see autotune using my EGTS instead of the o-2 sensor,so that I could go to each rpm and throttle position and say enter 1200 degree max temp and have it say be able to adjust with in 50 degrees each side of the 1200 . That would enhance the current Polaris system. I know what numbers work at different throttle positions with EGTS. Then you could go to reading pistons and plugs along with this much quicker. Just a wild idea,any thoughts guys?
 

thefullmonte

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For those of you questioning where to mount the O2 sensor bung. Here is where I had it mounted. The pipe is on the floor so it looks like the O2 sensor would be sitting straight up. It is not. The sensor is still at a slight angle. Did this as a just in case scenario for hood clearance.
picsforsnowest001.jpg

A big thanks again to Skinz Protective Gear. They did the install for me and re ceramic coated the stock pipe.
 
T
Dec 20, 2008
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cda id
Mountainhorse. Is there some feedback you can help me out on to get my struthers mod sled to run as good as you say they are running. Jack has sent us multiple ecms to try. They still have not lived up to my expectations. I just bought a pcv to see if i can get our sleds to run. Any suggestions other than that?
 
J

Jkinzer

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Nov 27, 2007
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Lewiston, Idaho
i know this isnt the ac section but its on the same subject with the pcV and the auto tune set up. we have an AC push turbo 2010 m8 that we have this set up on... havent had a chance to go run it yet... were hoping to yesterday but the shop was to busy so hopefully next friday. to the best of my knowledge after chatting with Steve and Ken we are pretty much the test bunnies on using this set up on a pump gas turbo set up. Dakota Performance has used it on multiple race gas turbo applications and has had good results so hopefully we find the same. COOL set up none the less. and it seems like a lot of guys are thinking that you can plug the system in and hit auto tune and with the A/F it jut takes care of everything and tunes itself... this is not the case. you must build your own base maps for the most part or refine one of theirs if they have one out (which they dont for a pump gas turbo at the moment) and get it relatively spot on. at which point you can then use the auto tune feature and will refine what you have already done
 
A

augerin

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Nov 26, 2007
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Kraven, I don't see the negativity here. I see two guy's that have a lot of great info to share and differing oppinions. My PC5 is on the way and the info in this thread will be a huge boost getting started. Thank's to all who have posted this is truely a great thread.
 

Kraven

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Kraven, I don't see the negativity here. I see two guy's that have a lot of great info to share and differing oppinions. My PC5 is on the way and the info in this thread will be a huge boost getting started. Thank's to all who have posted this is truely a great thread.

On the bold,

I think that guy is gone now.
 
E
Jan 18, 2008
503
96
28
St. Paul, AB
I think next season I might give the auto-tune a whirl on my 800, I have twin pipes so I plan on running a bung in each pipe, get a map based off each cylinder and then tune each cylinder based on the numbers the auto-tune comes up with(all while monitoring wash/egt of course). It will be very interesting to see how much of a difference there is between both cylinders/pipes plus the fact that the OEM pipe sensor only gets readings from one cylinder now, this new auto-tune idea is pretty awesome. Then once my sled is dialed in I will let my buddies use the auto-tune to get their maps dialed in.
 
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