Power Vision Information Thread
Outstanding HDF Member
Joined: Jan 2007
Posts: 2,598
Likes: 19
From: Naples FL / Pine TWP PA
As far as open loop goes that is just because you are moving the calibration around. It's like a torque wrench. If I calibrate 15ft lbs to 16ft lbs, every time I adjust the thing to 15ft lbs it is going to torque bolts to 16ft lbs. At least this is my understanding of it all.
Outstanding HDF Member
Joined: Jan 2007
Posts: 2,598
Likes: 19
From: Naples FL / Pine TWP PA
Well the may I am working on is the one that Dynojet told me to use for this bike with all the stuff I have on it. Maybe I should have used the stock one and let the software make suggestions to change that one.
I did 2 more runs this morning and the VE tables are changing going up and not down this time. I am using the narrow band sensors and the changes are only about 1 or less at a time. It sure would be nice to see 0 in the delta some time today.
Second Tank of Gas today! 195 Miles yesterday tuning!
I did 2 more runs this morning and the VE tables are changing going up and not down this time. I am using the narrow band sensors and the changes are only about 1 or less at a time. It sure would be nice to see 0 in the delta some time today.
Second Tank of Gas today! 195 Miles yesterday tuning!
Cruiser
Joined: Jan 2011
Posts: 125
Likes: 0
From: Rowlett, TX
Dynojets statments simply reflect the systems ability to tune much of the calibration without purchasing any additional equipment, however the Auto Tune module certainly works awesome for the higher load/upper RPM areas you cannot get to using the factory nbO2 sensors. You can use both sensors to create your tune, however when using Log Tuner Pro with the AT module I recommend setting up the calibration in open loop to avoid tuning around a "moving target'. I would change the cruise range in the AFR table to 13.8 and the Auto Tune will tune the full VE table. Once you have your tune logged and corrected with the widebands I would reinstall the factory O2 sensors and go back to the original AFR table with the closed loop enabled. If you choose to do so you can leave the AT module installed and use the widebands and monitor your tune right on the PV display in real time
I just received the WB O2 sensors and AT module, so your post was very timely... Just so I'm clear... You're suggesting we reinstall the NB O2 sensors just so we can run in closed loop mode... because with the AT module and WB sensors we can only run in open loop mode...is that correct? Thanks!
Art
Cruiser
Joined: Jan 2011
Posts: 125
Likes: 0
From: Rowlett, TX
So, for any given speed and pressure, the ECM reads the VE table and says.."well, it's going to pump .86 x 48 (for example) inches at this particular point, so I need "x" amount of fuel for that amount of volume". If you alter your VE table, and put in a bigger number, that tells the ECM that more air is being drawn into the engine, so more fuel is needed to maintain the correct AFR. The engine isn't REALLY drawing in more air...but the ECM believes the table, and adds the fuel anyway, and the mix gets richer as a result.
Cruiser
Joined: Mar 2009
Posts: 228
Likes: 0
From: Texas
It was explained to me this way... Your engine has a finite displacement...96cu in, or 103, or whatever.... But it isnt going to actually move its entire displacement every cycle...The VE table is a representation of how much of the total displacement the engine is actually moving. So if each cylinder were to actually pump 48c.i.(for a 96 inch engine) it's VE table would show 1 at that particular RPM and pressure.
So, for any given speed and pressure, the ECM reads the VE table and says.."well, it's going to pump .86 x 48 (for example) inches at this particular point, so I need "x" amount of fuel for that amount of volume". If you alter your VE table, and put in a bigger number, that tells the ECM that more air is being drawn into the engine, so more fuel is needed to maintain the correct AFR. The engine isn't REALLY drawing in more air...but the ECM believes the table, and adds the fuel anyway, and the mix gets richer as a result.
So, for any given speed and pressure, the ECM reads the VE table and says.."well, it's going to pump .86 x 48 (for example) inches at this particular point, so I need "x" amount of fuel for that amount of volume". If you alter your VE table, and put in a bigger number, that tells the ECM that more air is being drawn into the engine, so more fuel is needed to maintain the correct AFR. The engine isn't REALLY drawing in more air...but the ECM believes the table, and adds the fuel anyway, and the mix gets richer as a result.
I can see where this would be helpful, especially tuning in the closed-loop areas since any value lower than 14.6 in the AFR table will send the bike out of closed-loop into open-loop thus taking the NB O2 sensors out of operation. I guess you can only go so rich using the closed-loop Bias settings? Maybe thats why the VE tables are used to add fuel too in certain circumstances.
Outstanding HDF Member
Joined: Jan 2007
Posts: 2,598
Likes: 19
From: Naples FL / Pine TWP PA
Good explanation. This is the way I understand it as well. The ECM still tries to hit the AFR values in the AFR table, but adjusting the VE table basically tricks the ECM into thinking it needs more/less fuel than it really does to get the pre-defined AFR values.
I can see where this would be helpful, especially tuning in the closed-loop areas since any value lower than 14.6 in the AFR table will send the bike out of closed-loop into open-loop thus taking the NB O2 sensors out of operation. I guess you can only go so rich using the closed-loop Bias settings? Maybe thats why the VE tables are used to add fuel too in certain circumstances.
I can see where this would be helpful, especially tuning in the closed-loop areas since any value lower than 14.6 in the AFR table will send the bike out of closed-loop into open-loop thus taking the NB O2 sensors out of operation. I guess you can only go so rich using the closed-loop Bias settings? Maybe thats why the VE tables are used to add fuel too in certain circumstances.
6th Gear
Joined: Apr 2011
Posts: 10
Likes: 1
From: Rapid City, SD
It was explained to me this way... Your engine has a finite displacement...96cu in, or 103, or whatever.... But it isnt going to actually move its entire displacement every cycle...The VE table is a representation of how much of the total displacement the engine is actually moving. So if each cylinder were to actually pump 48c.i.(for a 96 inch engine) it's VE table would show 1 at that particular RPM and pressure.
So, for any given speed and pressure, the ECM reads the VE table and says.."well, it's going to pump .86 x 48 (for example) inches at this particular point, so I need "x" amount of fuel for that amount of volume". If you alter your VE table, and put in a bigger number, that tells the ECM that more air is being drawn into the engine, so more fuel is needed to maintain the correct AFR. The engine isn't REALLY drawing in more air...but the ECM believes the table, and adds the fuel anyway, and the mix gets richer as a result.
So, for any given speed and pressure, the ECM reads the VE table and says.."well, it's going to pump .86 x 48 (for example) inches at this particular point, so I need "x" amount of fuel for that amount of volume". If you alter your VE table, and put in a bigger number, that tells the ECM that more air is being drawn into the engine, so more fuel is needed to maintain the correct AFR. The engine isn't REALLY drawing in more air...but the ECM believes the table, and adds the fuel anyway, and the mix gets richer as a result.
That is why I am a little confused, The stock bike was said to be very lean so when you change pipes, Air cleaner it would allow better flow or more air volume into the motor and out of the motor. So it would be leaner yet!
So when I do my logs and it suggests that the cells be changed to a lower reading than the stock settings it confused me.
I put on a SE air cleaner, Changed header pipe to S & S power Duals and the Mufflers are the S & S SPO Mufflers.
So of course I would think that I would be higher. When I do a Delta between the Map that Dynojet suggested to use and after several Tunes I have cells that have as much as 18 difference.
Thanks again for all the help.
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Outstanding HDF Member
Joined: Jan 2007
Posts: 2,598
Likes: 19
From: Naples FL / Pine TWP PA
That is why I am a little confused, The stock bike was said to be very lean so when you change pipes, Air cleaner it would allow better flow or more air volume into the motor and out of the motor. So it would be leaner yet!
So when I do my logs and it suggests that the cells be changed to a lower reading than the stock settings it confused me.
I put on a SE air cleaner, Changed header pipe to S & S power Duals and the Mufflers are the S & S SPO Mufflers.
So of course I would think that I would be higher. When I do a Delta between the Map that Dynojet suggested to use and after several Tunes I have cells that have as much as 18 difference.
Thanks again for all the help.
So when I do my logs and it suggests that the cells be changed to a lower reading than the stock settings it confused me.
I put on a SE air cleaner, Changed header pipe to S & S power Duals and the Mufflers are the S & S SPO Mufflers.
So of course I would think that I would be higher. When I do a Delta between the Map that Dynojet suggested to use and after several Tunes I have cells that have as much as 18 difference.
Thanks again for all the help.
Advanced
Joined: May 2011
Posts: 66
Likes: 0
Has anyone else noticed their motor pinging but have no knock retard show up in the datalogs?? Some of my logs show no knock retard when I have definitely heard a pinging. Some logs do show the ping. It is kinda odd... So unless there is something out there that sounds EXACTLY like pinging that isn't actual ping, then the ECM/PV/or Plugs aren't picking it up.
Anyone else notice this?
Anyone else notice this?