LockedDobeck 3.5 question

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TunerBoy
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Re:Dobeck 3.5 question 2012/09/28 22:21:38 (permalink)
I just went back to the other question. How the OEM map was created and what it all consist of is too vague of a question without writing a book to answer it.
 
Canam has a 3rd party do it for them. Whether they use an engine dyno, chassis dyno, pressure equipment, 4 gas, 5 gas, 1 gas widebands, exhaust temp or all of the above is anyones guess.
 
post edited by TunerBoy - 2012/09/28 22:23:15
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Re:Dobeck 3.5 question 2012/09/29 10:30:18 (permalink)
^^^ Exactly.  
 
The only way i can think of to answer your question maddog is as follows... The stock ecm calculates fueling based on a lot of variables.  It uses rpm, throttle position, MAP sensor reading, iat, coolant temp, ect to calculate the injector pw.  Heck, it may even consider the rate of change of rpm in its final pw calculation.  I dont know...
 
Greg - the reason the PC is not very effective is it bases its fueling only off of two variables, rpm and tp.  It is more effective to base your fuel map off of the pw vs. rpm since you are changing the pw and it is the final calculated value of the ecm.  The power commander looks at tp, which is only one of the variables used in calculating pulse width.  No matter what the pw is from the ecm, at a given throttle position and rpm the power commander will only add a preset amount of fuel.  Also, the pw from the ecm changes with different iat's (intake air temperature), elevation (map sensor reads that), etc.  The pc has no way of adjusting for that only adjusting fuel for throttle position and rpm.
 
The Dobeck on the other hand splits the fuel table into three ranges based on pw and rpm.  No matter what the pw is the dobeck will only add a preset amount of fuel within each range.  The thing is... even though the dobeck uses a better tuning methodology with pw vs rpm... under most circumstances the pw does not change enough at a given tp and rpm to make the dobeck change ranges.  Chances are, if you are running at 50% throttle at 4000 rpm on a slight uphill climb (and you are in the middle of the middle range of the dobeck), even though the pw is going to change if you are in deep mud with 32s, or going down a hill with very little load on the bike, the difference in pw is probably not going to be enough to make the dobeck use one of the other ranges.  In all 3 circumstances the dobeck is going to still be in the middle range adding the same preset amount of fuel.
 
Here is a good thread with info about his: 
http://www.can-amtalk.com/forums/topic/30808-what-is-load-based-tuning/page__st__60
 
There is good info in the entire thread, but page 4 was the most revealing for me.
 
 
 
 
 
 

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Re:Dobeck 3.5 question 2012/09/29 10:52:58 (permalink)
You were really close on your answer until you said "I don't know", thats alot to say and not know.  So, whether you do or not thats close enough.
 
But you dont know how a dobeck works, its a very complex software not a rheostat with a set value like your stating.
 
We'll let the engineer divulge that part of it.

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Re:Dobeck 3.5 question 2012/09/29 11:21:44 (permalink)
Fair enough.
 
When i said i dont know... I meant i dont know all of the variables the ecm uses to calculate the pw.  However i stand behind everything else i said as correct.
 
Looking forward to the engineers response.  
 
 

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Re:Dobeck 3.5 question 2012/09/29 12:16:14 (permalink)
Its a static value in 3 zones, weighted by one or a combination of input and rpm for each. It acts as an adjustable rheostat between each zone at the switchpoints. A by product of specific setup on the 3 zones may overlap any zones, in which adding those zone effects all together. To the limit of the maximum allowed output.
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Re:Dobeck 3.5 question 2012/09/30 15:47:21 (permalink)
kleinwild

DobekFTW... I'm really impressed with mine.

 
I agree 110% with that one.
 
If you want a out of box tuner that will put yuor bike in a Safe range right off the Bat. Dobeck it is..
 
I was shocked with the Widebands reading on mine.  12.6 At idle right off the bat.  Thats pretty dang impressive to me. simple changes and now its 12.8-12.9
 
My bike is not stock either. 
 
AS Dk said DOBEKFTW

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Re:Dobeck 3.5 question 2012/09/30 16:09:49 (permalink)
chrisgrizzly660

kleinwild

DobekFTW... I'm really impressed with mine.


I agree 110% with that one.

If you want a out of box tuner that will put yuor bike in a Safe range right off the Bat. Dobeck it is..

I was shocked with the Widebands reading on mine.  12.6 At idle right off the bat.  Thats pretty dang impressive to me. simple changes and now its 12.8-12.9

My bike is not stock either. 

AS Dk said DOBEKFTW

 
So you are shocked that you were able to get your idle dialed in with a fuel controller? lol
 
I agree, the debeck is without a doubt the easiest, quickest, and most cost effective way to get your bike in the safe range.  Is that your only criteria though?  What is the easiest to get in the "safe range"?  
 
btw, i recommend tuning for more than just idle.
 
 
post edited by DSCZ71 - 2012/09/30 16:22:13

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Re:Dobeck 3.5 question 2012/09/30 16:27:38 (permalink)
Nick im starting to think you have stock in steves products! Lol.... kidding of course

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Re:Dobeck 3.5 question 2012/09/30 16:45:40 (permalink)
stingertrey

Nick im starting to think you have stock in steves products! Lol.... kidding of course

 
Yep, i also have stock in can-am products.  Why else would i ride a can am and recommend them to others?? 
 
I would much rather spend $225 for a fuel controller than $400.  If i believed they were both equally as effective.
 
Also, i have been doing my best to keep my post relevant to the current topic at hand (there have been lots of different topics in this thread).  Instead of saying Fuel Monster FTW!! I have been trying to keep my posts about the facts.
post edited by DSCZ71 - 2012/09/30 16:56:29

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Re:Dobeck 3.5 question 2012/09/30 17:00:04 (permalink)
Yea I have been reading along bc you guys are far more advanced in tuning than I am

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Re:Dobeck 3.5 question 2012/09/30 17:01:59 (permalink)
DSCZ71

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kleinwild

DobekFTW... I'm really impressed with mine.


I agree 110% with that one.

If you want a out of box tuner that will put yuor bike in a Safe range right off the Bat. Dobeck it is..

I was shocked with the Widebands reading on mine.  12.6 At idle right off the bat.  Thats pretty dang impressive to me. simple changes and now its 12.8-12.9

My bike is not stock either. 

AS Dk said DOBEKFTW


So you are shocked that you were able to get your idle dialed in with a fuel controller? lol

I agree, the debeck is without a doubt the easiest, quickest, and most cost effective way to get your bike in the safe range.  Is that your only criteria though?  What is the easiest to get in the "safe range"?  

btw, i recommend tuning for more than just idle.



 
No  I was impressed at how well it worked with my motor and all the mods it has done to it.  I can tell you this I have tuned alot of canams and other bikes with PC3/ PC5 and the dobeck is alot easier to work with and operate.  Power commander was not even close to what this one is. Ride all over the place watching wideband and adjusting, and then repeat,  You know the drill. If you want simplicity get the dobeck, install and ride.  I cant speak for thee one you are running as I dont own it. All I know is this one works and works well. All the way to 100% throttle its reading good numbers. 
 
Just out of curisity how many have you tuned in the past with a Power commander? it sucks to say the least
 
oh and mine isnt tuned just at idle Its tuned all the way to hang on DA. lol 

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Re:Dobeck 3.5 question 2012/09/30 17:08:23 (permalink)
Oh ok i gotcha!
 
I have never tuned a bike with a pcv.  Just knowing how they work and reading how-to articles explaining how to tune them and how it takes hours upon hours to tune them even with autotune is enough to make me not want to mess with them.  
 
What mods do you have done to your bike?  Glad you like it and it is working well for you!
 
 
post edited by DSCZ71 - 2012/09/30 17:15:35

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Re:Dobeck 3.5 question 2012/09/30 17:20:35 (permalink)
As far as performance its got 840, cams, intake, piped, snorked, etc. 
 
Tuniing a PC is just time consuming and takes a while.
 
 It seems you are having good luck with the FM and I am having great luck with the 3.5.  Both seem to be capable tuners and will work for you.
 
 
 
 

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Re:Dobeck 3.5 question 2012/10/04 23:43:44 (permalink)
Maddog, im anxiously awaiting the engineer's response/explanation! 
post edited by DSCZ71 - 2012/10/04 23:46:19

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Re:Dobeck 3.5 question 2012/10/05 00:17:58 (permalink)
Don't have any explanation but I did order gorillas programmer and installed it on my bike. Runs smoother. Had it in a sink hole/old thick pond and it didn't seem to hesitate the least bit when I mashed on it.


Had maddog set it up for me and it works great. Was keeping a good a/f ratio through all the rpm ranges when installed. I knew my bike was running lean just by listening to it before, but didn't think it was that bad. It sounds an feels like it's running a lot better.

I'm satisfied, especially for the money.

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Re:Dobeck 3.5 question 2012/10/05 05:41:14 (permalink)
The guys trying to finish an r&d project this week, I'll check to see if he is free yet.

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Re:Dobeck 3.5 question 2012/10/05 09:47:26 (permalink)
I have 10,000 reasons that I go with nothing but Dobeck.

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Re:Dobeck 3.5 question 2012/10/05 12:50:26 (permalink)
Thats whats up MBB!
 
Thanks maddog!
 
DK - lol sounds like plenty reasons to continue going with nothing but Dobeck!
 
I remember reading a post by DK that said something like... "Im not the kind of guy who cares what makes a clock tick, i just want to know what time it is".  
 
Haha i had never heard that before but i love it!  However, as a 5th year engineering student I have been transformed  into the kind of guy who must know what makes a clock tick. With engineers, engine builders, tuners, ect. you dont have to worry about "what makes a clock tick" if you dont want to.  You can just enjoy knowing what time it is! 
 
 

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Re:Dobeck 3.5 question 2012/10/05 14:03:25 (permalink)
All 12 engineers I work with say the same thing... Its drives them nuts when I tell them that lol
 
Its always Dobeck:30 at my shop...

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Re:Dobeck 3.5 question 2012/10/05 18:35:53 (permalink)
i can tune a carb pretty close but i cant even tell you how to hook up a fuel programmer. the single thing i miss most about hondas... and old trucks :D
 
back on topic, how much is a dobeck running for atm? might need to get a programmer soon.

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Re:Dobeck 3.5 question 2012/10/05 18:43:48 (permalink)
The gorilla efi (dobeck) tuner is at a very good price of $225

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Re:Dobeck 3.5 question 2012/10/05 18:48:46 (permalink)
dang thats cheap

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Re:Dobeck 3.5 question 2012/10/05 20:38:51 (permalink)
Yelp. It works awesome.

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Re:Dobeck 3.5 question 2012/10/08 10:55:20 (permalink)
Hello everyone,
I would like to post the following information to hopefully clear up some of the questions presented in this thread.
Fuel Injection Base Maps, Fuel Calculation Sequence and Closed Loop Tuning
 
When a vehicle is first produced at a manufacturer, a base map is needed for the ECU so that the engine can be run.  This is done by calculating the engine VE (Volumetric Efficiency) at varying load points and RPM’s.  Using fully characterized fuel injectors, operating at a set fuel pressure, one can then safely calculate the injector pulse width required to keep the engine at a certain AFR.  This data is then stored as the “Base Map” for this vehicle.
 
Here is a great resource explaining the calculations required to get a desired AFR based on reading the engine sensors to calculate the current engine VE, and thus output injector pulse width:  Fuel Calculation Link.
 
The Dobeck fuel controller uses the input from the fuel injector as a means of getting its data.  Using this input, 4 parameters are extracted and used for internal mapping and switch points: RPM, change in RPM, injector pulse width, and change in injector pulse width.
 
Using this data, a map is then created for each specific vehicle application and thus a “base map” is created for use in the Dobeck fuel controller.  Some maps use RPM and Pulse width only, while others use changes in RPM and Pulse width to trigger certain events, ranges, modes, etc.
 
The Dobeck Gen 4 controller running in Closed Loop mode uses the same theory as the OEMs use to develop base fuel maps.  An AFR is measured and appropriate action is taken to keep the vehicle at a certain desired AFR.
 
As an engine accelerates and decelerates the fuel quantity to achieve this desired AFR also changes.  On CVT operated vehicles the clutch is loading the engine so that the vehicle is running at maximum power as much as possible, thus keeping RPM’s at a relatively constant value.  This is a “steady state” condition as far as the controller is concerned, as injector pulse width is really the only variable that is changing significantly at this point. 
 
The Gen 4 fuel controller uses a sophisticated algorithm to calculate the fuel output required to achieve the user’s desired AFR value set for a given mode.  The AFR value read by the controller is the result of the previous combustion event, however using changes in RPM and pulse width, the controller knows if the vehicle is increasing or decreasing in engine load.  When using this additional data the closed loop control in real time is very accurate and results in “Real Time Closed Loop Tuning”, therefore the need for extra look-ups and trim tables are not needed.
 
Thank you,
Dobeck Performance
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Re:Dobeck 3.5 question 2012/10/08 11:19:48 (permalink)
I was doing pretty good until I clicked on the link and started reading, lol.  

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Re:Dobeck 3.5 question 2012/10/08 12:22:21 (permalink)
Wow, that was awesome.  Thanks Dobeck!!  I appreciate you taking the time to explain this to us.  
 
I have a couple additional questions right off the bat.  Im sure i will have more as i have time to think about this and absorb all of the information you posted.
 
"Using this data, a map is then created for each specific vehicle application and thus a “base map” is created for use in the Dobeck fuel controller."
 
Let me ask you this.  When you say a base map is created... The base map created is really just the oem base map overlayed with 3 separate ranges.  The user can adjust the amount of fuel added for each range.  So the base map that is created is the oem base map plus a certain amount of fuel.  The base map made by the dobeck after it is programmed is really nothing more than the oem base map cut into 3 sections and a set amount of fuel is added to each section. Is that correct?
 
I understand that the shape/size of each section is highly customizable via dobecks powerlab program by tuners.  They can control the switch points of the 3 ranges and when each range is used based on rpm, pw, change in rpm, and change in pw.  However, the end result is the oem base fuel map plus a certain percentage of fuel (and there are only 3 different "certain percentages of fuel").
 
So does that mean that you can effectively divide an entire fuel map into 3 separate ranges and every rpm and pw value within each range needs the same amount of additional fueling?  
 
If so, why would the gen 4 closed loop feature be necessary?  And why does dynojet use 200+ cells in their power commander fuel maps if 3 ranges would be enough?   How is the dobeck more effective than the power commander even though the power commander has so much more resolution?  
 
Thank you for your time!!  Sure is nice to have an expert take the time to answer our questions!
 
Ohh another question: Do you have an OEM VE table you could post?  Im curious as to how efficient these motors are in stock form.
 
 
post edited by DSCZ71 - 2012/10/08 12:34:32

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Re:Dobeck 3.5 question 2012/10/08 12:44:53 (permalink)
Dobeck Performance 
When a vehicle is first produced at a manufacturer, a base map is needed for the ECU so that the engine can be run.  This is done by calculating the engine VE (Volumetric Efficiency) at varying load points and RPM’s.  

 
WAY BAD
I'll take a stab...
The amount of fuel for the said Volumetric Efficiency of the egine based on RPM.

 
I was pretty dang close with my answer on how the Mfg. gets it's base map back on page 2...


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Re:Dobeck 3.5 question 2012/10/08 13:05:35 (permalink)
Oh, and will the closed loop tuning will be active for all ranges at the same time?
 
WAY BAD - You sure were!!  Spot on man.
 
My answer and your answer put together would be it.  The VE efficiency table is created based on how much air can fit in the cylinder (the displacement) vs how much air actually gets sucked into the cylinder at a certain rpm and map (the higher the pressure the more air that will get sucked in).  However, you must know more than just the amount of air in the cylinder to calculate how much fuel is needed.  Thats where the other sensors come into play.  Cooler air is denser and therefore requires more fuel per unit volume of air.  
 
So im guessing that the ecm calculates the pw (required amount of fuel) based on the VE table and then that value is modified by the other sensors.  I assume there is some kind of formula for how much the VE table value is modified based on the sensor readings.
post edited by DSCZ71 - 2012/10/08 13:15:12

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Re:Dobeck 3.5 question 2012/10/08 13:41:48 (permalink)
Dobeck - what happens if the o2 sensor fails?   Also, does the closed loop real time tuning apply for all 3 ranges or just one range?
post edited by DSCZ71 - 2012/10/08 14:53:40

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Re:Dobeck 3.5 question 2012/10/08 16:34:38 (permalink)
DSCZ71

WAY BAD - You sure were!!  Spot on man.

My answer and your answer put together would be it.  The VE efficiency table is created based on how much air can fit in the cylinder (the displacement) vs how much air actually gets sucked into the cylinder at a certain rpm and map (the higher the pressure the more air that will get sucked in).  However, you must know more than just the amount of air in the cylinder to calculate how much fuel is needed.  Thats where the other sensors come into play.  Cooler air is denser and therefore requires more fuel per unit volume of air.  

So im guessing that the ecm calculates the pw (required amount of fuel) based on the VE table and then that value is modified by the other sensors.  I assume there is some kind of formula for how much the VE table value is modified based on the sensor readings.

 
Agreed sir!


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