WOT Tuning without a Wideband - UPDATED
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Joined: Jul 2002
Posts: 1,277
From: Phoenix, AZ
WOT Tuning without a Wideband - UPDATED
Some of you may remember a post I did a few years back:
http://web.camaross.com/forums/showthread.php?t=143169
For all the details, please take a look and you will understand better what I was able to accomplish now.
UPDATE:
When I dynoed with the tailpipe wideband, I assumed I was not accurate because of my cat. It has taken me this long to find a place that had a wideband to put right into my bung on the collector BEFORE the cat.
Additionally, here is what I have done to make sure I have limited the factors affecting the wideband results:
Injectors pulled and serviced to put all within +/- 2% flowrate
MAF sensor cleaned
Find all exhaust leaks prior to O2's
Recalibration of MAF
Same fuel from same gas station used to dyno and with calibrating MAF – to avoid variances in fuel BTU values.
BLM locker programmed in
I set my AFR for 12.5:1 and zeroed out my "%change to Fuel/Air ratio Vs. RPM at WOT" on TunerCat. From the beginning of the pull until shutoff, I averaged 12.6 AFR with a variance of +/- 0.25. I averaged less than 1% variance from the AFR I had tuned into the computer.
I can now without a doubt say that my technique does work...for me.
http://web.camaross.com/forums/showthread.php?t=143169
For all the details, please take a look and you will understand better what I was able to accomplish now.
UPDATE:
When I dynoed with the tailpipe wideband, I assumed I was not accurate because of my cat. It has taken me this long to find a place that had a wideband to put right into my bung on the collector BEFORE the cat.
Additionally, here is what I have done to make sure I have limited the factors affecting the wideband results:
Injectors pulled and serviced to put all within +/- 2% flowrate
MAF sensor cleaned
Find all exhaust leaks prior to O2's
Recalibration of MAF
Same fuel from same gas station used to dyno and with calibrating MAF – to avoid variances in fuel BTU values.
BLM locker programmed in
I set my AFR for 12.5:1 and zeroed out my "%change to Fuel/Air ratio Vs. RPM at WOT" on TunerCat. From the beginning of the pull until shutoff, I averaged 12.6 AFR with a variance of +/- 0.25. I averaged less than 1% variance from the AFR I had tuned into the computer.
I can now without a doubt say that my technique does work...for me.
Last edited by 95Blackhawk; Feb 27, 2007 at 06:51 PM.
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Joined: Feb 2000
Posts: 1,009
From: Cincinnati, OH, USA
Great to hear it verified!
I always thought it was good logic and did it myself. I plan to do it again now that I have a new cam installed along with a ZO6 MAF sensor. I'm sure those two things will really call for fine-tuning the MAF tables.
Found any good methods for tuning/evaluating timing advance changes?
I always thought it was good logic and did it myself. I plan to do it again now that I have a new cam installed along with a ZO6 MAF sensor. I'm sure those two things will really call for fine-tuning the MAF tables.
Found any good methods for tuning/evaluating timing advance changes?
Thread Starter
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Joined: Jul 2002
Posts: 1,277
From: Phoenix, AZ
The dyno is the only way I am aware of. I just put in different values across the board and saw where my torque fell or rose depending upon what the timing was. I started at 32* from 2K up and did a pull. Then I went to 35* and repulled. My torque increased in the 4K range and above with the higher timing but none in the lower range. No reason for me to go above this as I am sitting at the edge of predenotation now.
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Joined: Dec 2004
Posts: 66
I have tunercats, and have done some limited dyno tuning. I have always made my WOT changes in the % change to A/F vs RMP @ WOT. Unlike LS1s our cars can not make changes at wot from O2 readings. The table that your making changes in will change the WOT A/F, but un less the car is bone stock that table is going to be off. The only way I could see your way of tuning working is if the car was 100% bone stock. If your A/F was close to the numbers you entered into that table, I would have to say it was only a coincidence.
I would love for you to prove me wrong, because I need to make a new tune for my new cam setup, and I would love the tuning to be that easy.
I would love for you to prove me wrong, because I need to make a new tune for my new cam setup, and I would love the tuning to be that easy.
Thread Starter
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Joined: Jul 2002
Posts: 1,277
From: Phoenix, AZ
The table that your making changes in will change the WOT A/F, but un less the car is bone stock that table is going to be off. The only way I could see your way of tuning working is if the car was 100% bone stock. If your A/F was close to the numbers you entered into that table, I would have to say it was only a coincidence.
Please clarify.
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Joined: Feb 2000
Posts: 1,009
From: Cincinnati, OH, USA
It would appear he didn't read the original post and doesn't realize what you did with the MAF tables. That's my guess.
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Joined: May 2005
Posts: 192
From: San Antonio, TX
+1 If anyone around my area would like to give me some tuning tips (hint hint JSK333) I would gladly accept as I am going to attempt to tune my car after my recent longtube install. Also, if anyone has any .bin or .lt1 files they would like to send me to look at different tuning techniques, please pm me. Should be fun and goes along with my mechanical engineering degree in progress.
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Joined: Jun 2003
Posts: 3,620
From: Saginaw, Michigan
Guys,
I've learned quite a bit since Ben and I were tossing this around. Having a wideband now makes it easier.
When I tried this on my Z, I changed all of the maf tables so that I had the cell 15 blm as close to 128 as I could and assumed that I had achieved a 14.7:1 a/f ratio. I then added the correct amount of fuel to get the a/f ratio in pe to 12.8:1. No reason why I picked that number, just thought it was a good place to shoot for.
Problem was, I was getting knock all over the place. No matter what I did I was getting knock at wide open throttle. No amount of adding fuel or pulling timing would get rid of it.
Went back to stock maf tables, used the same timing, and made my guess as to what to have in the pe table and guess what...no more knock. Injector pulsewidths were nearly identical as with the "corrected" maf tables, so I assume I had roughly the same amount of fuel in it.
I just wish I would have had the wideband when I did this experimenting.
Now that I do have it, and this topic got brought back up, I wish I still had the Z so that I could go do some more testing.
I've learned quite a bit since Ben and I were tossing this around. Having a wideband now makes it easier.
When I tried this on my Z, I changed all of the maf tables so that I had the cell 15 blm as close to 128 as I could and assumed that I had achieved a 14.7:1 a/f ratio. I then added the correct amount of fuel to get the a/f ratio in pe to 12.8:1. No reason why I picked that number, just thought it was a good place to shoot for.
Problem was, I was getting knock all over the place. No matter what I did I was getting knock at wide open throttle. No amount of adding fuel or pulling timing would get rid of it.
Went back to stock maf tables, used the same timing, and made my guess as to what to have in the pe table and guess what...no more knock. Injector pulsewidths were nearly identical as with the "corrected" maf tables, so I assume I had roughly the same amount of fuel in it.
I just wish I would have had the wideband when I did this experimenting.
Now that I do have it, and this topic got brought back up, I wish I still had the Z so that I could go do some more testing.
Dan
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Joined: Apr 1999
Posts: 95
From: Albertville,AL
Some of you may remember a post I did a few years back:
http://web.camaross.com/forums/showthread.php?t=143169
For all the details, please take a look and you will understand better what I was able to accomplish now.
UPDATE:
When I dynoed with the tailpipe wideband, I assumed I was not accurate because of my cat. It has taken me this long to find a place that had a wideband to put right into my bung on the collector BEFORE the cat.
Additionally, here is what I have done to make sure I have limited the factors affecting the wideband results:
Injectors pulled and serviced to put all within +/- 2% flowrate
MAF sensor cleaned
Find all exhaust leaks prior to O2's
Recalibration of MAF
Same fuel from same gas station used to dyno and with calibrating MAF – to avoid variances in fuel BTU values.
BLM locker programmed in
I set my AFR for 12.5:1 and zeroed out my "%change to Fuel/Air ratio Vs. RPM at WOT" on TunerCat. From the beginning of the pull until shutoff, I averaged 12.6 AFR with a variance of +/- 0.25. I averaged less than 1% variance from the AFR I had tuned into the computer.
I can now without a doubt say that my technique does work...for me.
http://web.camaross.com/forums/showthread.php?t=143169
For all the details, please take a look and you will understand better what I was able to accomplish now.
UPDATE:
When I dynoed with the tailpipe wideband, I assumed I was not accurate because of my cat. It has taken me this long to find a place that had a wideband to put right into my bung on the collector BEFORE the cat.
Additionally, here is what I have done to make sure I have limited the factors affecting the wideband results:
Injectors pulled and serviced to put all within +/- 2% flowrate
MAF sensor cleaned
Find all exhaust leaks prior to O2's
Recalibration of MAF
Same fuel from same gas station used to dyno and with calibrating MAF – to avoid variances in fuel BTU values.
BLM locker programmed in
I set my AFR for 12.5:1 and zeroed out my "%change to Fuel/Air ratio Vs. RPM at WOT" on TunerCat. From the beginning of the pull until shutoff, I averaged 12.6 AFR with a variance of +/- 0.25. I averaged less than 1% variance from the AFR I had tuned into the computer.
I can now without a doubt say that my technique does work...for me.
Thanks!
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Joined: Dec 2005
Posts: 372
After reading over all of this info and annylizing it a bit I've come up with a few questions to make things a tad clearer for me.
1. In what table did you "set my AFR for 12.5:1"? Or did you use a wideband in conjunction with the "%change to Fuel/Air ratio Vs. RPM at WOT" to get the ratio to 12.5:1(closed loop)? This is the method I plan to use after calibrating the MAF.
2. By zeroed out your "%change to Fuel/Air ratio Vs. RPM at WOT" table do you mean you put all zeroes in the table?
3. Also if I understand correctly after locking your BLM's you can make your pcm read off the WOT tables only by setting the "MAP Threshold to Enable WOT" table to 255. If I am correct does it realy matter what your MAP is reading at this time while tuning the MAF?
4. Also you speak of not having a linear perspective on your MAF table after your calibrations. Wouldn't this be due to the long term block learn of the PCM if you did not reset it given that there are already long term algorithms in affect even after you lock out the BLM's? If you Disconnect the battery and reset the pcm prior to locking the BLM's then tune the MAF to read correctly wouldn't this negate the block learns that are stored in the pcm prior and result in a more accurate/linear MAF tune?
I am by no means the expert here and am asking these question to make it more clear to me before I start my own wideband tuning with Tunercat/FJO Wideband/Datamaster.
1. In what table did you "set my AFR for 12.5:1"? Or did you use a wideband in conjunction with the "%change to Fuel/Air ratio Vs. RPM at WOT" to get the ratio to 12.5:1(closed loop)? This is the method I plan to use after calibrating the MAF.
2. By zeroed out your "%change to Fuel/Air ratio Vs. RPM at WOT" table do you mean you put all zeroes in the table?
3. Also if I understand correctly after locking your BLM's you can make your pcm read off the WOT tables only by setting the "MAP Threshold to Enable WOT" table to 255. If I am correct does it realy matter what your MAP is reading at this time while tuning the MAF?
4. Also you speak of not having a linear perspective on your MAF table after your calibrations. Wouldn't this be due to the long term block learn of the PCM if you did not reset it given that there are already long term algorithms in affect even after you lock out the BLM's? If you Disconnect the battery and reset the pcm prior to locking the BLM's then tune the MAF to read correctly wouldn't this negate the block learns that are stored in the pcm prior and result in a more accurate/linear MAF tune?
I am by no means the expert here and am asking these question to make it more clear to me before I start my own wideband tuning with Tunercat/FJO Wideband/Datamaster.
Thread Starter
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Joined: Jul 2002
Posts: 1,277
From: Phoenix, AZ
If I do a screenshot, what is it you are looking for? My BLMS are locked at 128 so nothing to show there. If there are specifics, I am glad to show.
Ben
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Joined: Jul 2002
Posts: 1,277
From: Phoenix, AZ
1. In what table did you "set my AFR for 12.5:1"? Or did you use a wideband in conjunction with the "%change to Fuel/Air ratio Vs. RPM at WOT" to get the ratio to 12.5:1(closed loop)? This is the method I plan to use after calibrating the MAF.
2. By zeroed out your "%change to Fuel/Air ratio Vs. RPM at WOT" table do you mean you put all zeroes in the table?
3. Also if I understand correctly after locking your BLM's you can make your pcm read off the WOT tables only by setting the "MAP Threshold to Enable WOT" table to 255. If I am correct does it realy matter what your MAP is reading at this time while tuning the MAF?
4. Also you speak of not having a linear perspective on your MAF table after your calibrations. Wouldn't this be due to the long term block learn of the PCM if you did not reset it given that there are already long term algorithms in affect even after you lock out the BLM's? If you Disconnect the battery and reset the pcm prior to locking the BLM's then tune the MAF to read correctly wouldn't this negate the block learns that are stored in the pcm prior and result in a more accurate/linear MAF tune?
2. By zeroed out your "%change to Fuel/Air ratio Vs. RPM at WOT" table do you mean you put all zeroes in the table?
3. Also if I understand correctly after locking your BLM's you can make your pcm read off the WOT tables only by setting the "MAP Threshold to Enable WOT" table to 255. If I am correct does it realy matter what your MAP is reading at this time while tuning the MAF?
4. Also you speak of not having a linear perspective on your MAF table after your calibrations. Wouldn't this be due to the long term block learn of the PCM if you did not reset it given that there are already long term algorithms in affect even after you lock out the BLM's? If you Disconnect the battery and reset the pcm prior to locking the BLM's then tune the MAF to read correctly wouldn't this negate the block learns that are stored in the pcm prior and result in a more accurate/linear MAF tune?
2. Yes
3. Locking BLM's is used in WOT. BLM's don't lock when you set the "MAP Threshold to Enable WOT" table to 255. You do that to determine where to modify your MAF sensor calibration tables.
4. I read that 2 times and still do not understand what you are asking. Please ask again and I will answer.
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Joined: Feb 2000
Posts: 178
From: Toronto, Ontario, Canada
There was a question in the previous post regarding whether this would work with VE tables for speed density vehicles. These tables would be a lot easier to adjust, I assume, as we can use VE master to take care of it.
The second question I have is.... is it necessary to go WOT without going into PE to calibrate the MAF. If I log a bunch of data I can get for each BLM for each cell what the MAF is reading. I can then filter for a few cells (ie. 15, 14, 13) and see what the MAF is reading versus the BLM's... can I not then just trend them to get what the MAF needs to be to get the BLM's to 128? Why does cell 15 need to be used?
The second question I have is.... is it necessary to go WOT without going into PE to calibrate the MAF. If I log a bunch of data I can get for each BLM for each cell what the MAF is reading. I can then filter for a few cells (ie. 15, 14, 13) and see what the MAF is reading versus the BLM's... can I not then just trend them to get what the MAF needs to be to get the BLM's to 128? Why does cell 15 need to be used?
Thread Starter
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Joined: Jul 2002
Posts: 1,277
From: Phoenix, AZ
There was a question in the previous post regarding whether this would work with VE tables for speed density vehicles.
The second question I have is.... is it necessary to go WOT without going into PE to calibrate the MAF?? If I log a bunch of data I can get for each BLM for each cell what the MAF is reading. I can then filter for a few cells (ie. 15, 14, 13) and see what the MAF is reading versus the BLM's... can I not then just trend them to get what the MAF needs to be to get the BLM's to 128? Why does cell 15 need to be used?
The second question I have is.... is it necessary to go WOT without going into PE to calibrate the MAF?? If I log a bunch of data I can get for each BLM for each cell what the MAF is reading. I can then filter for a few cells (ie. 15, 14, 13) and see what the MAF is reading versus the BLM's... can I not then just trend them to get what the MAF needs to be to get the BLM's to 128? Why does cell 15 need to be used?
On your second question, look at it from this standpoint: We want to calibrate the MAF tables. How you do this is up to you. If you don't want to confirm the whole MAF range that your car works in, that is fine but I wouldn't. PE mode and WOT are used interchangeably here on this forum and they should not be. I was at WOT when I tested but my car never went into PE mode.
Cell 15 is used because it is generally where people are at the highest RPM and MAP and where 75% of the MAF range is used. Don't get hung up on cells. focus on calibration of the MAF.
Last edited by 95Blackhawk; Aug 2, 2007 at 01:29 PM.