Ok When I get my LTFT's Dialed in ,now do I do the same for STFT's?
05-22-2005, 09:39 AM
#1
Ok When I get my LTFT's Dialed in ,now do I do the same for STFT's? Do I then do the Same proceedures for the STFT's as I did with the LTFT's?Do I stay in SD Mode for STLT's?I dont mean to jump the gun here,But IF I do indeed get my LTFT's dialed in today,I want to get this Finished asap.
Thanks!
Thanks!
Last edited by Pro Mouse; 05-22-2005 at 09:44 AM.
05-22-2005, 10:17 AM
#2
Tuning With STFT’s Alone
Now things get quite a bit easier, because we no longer have to wait for LTFT’s to be learned. First off, open the editor and go to General>Fuel Control>Open & Closed Loop, and set LTFT enable to “OFF”. Then go to General>Fuel Control>Power Enrich. Look for the MAP field under the “PE Enable” heading, and set it to 640 (This will disable PE mode. We don’t want it interfering with our next step). Save these parameters and load it onto your PCM. Now we get to do some more logging.
Method here becomes very important. We want to start out by getting the vehicle up to operating temp, like always. Try to find a long stretch of road with no stops. A high speed limit here also helps. Start the STFT histogram as you’ll be referencing it quite a lot while you’re driving, and start logging. Get into third gear (for an M6, if you have an A4 you may have to experiment to find a gear that works well for the following procedure), and level the RPM’s off at about 1200. Now, we’re going to “pulse” the gas pedal, constantly going from 0 – 100% TPS (this is why we disable PE mode) at a steady rate. This can be a bit tricky, but the object is to hit every MAP cell for the 1200 RPM column from off-idle to WOT. You should be able to cycle through the column a couple times before the engine falls into the 1600 RPM column. Continue doing this for all subsequent RPM columns. If you plan on using your MAF again after tuning your VE table, you can stop if you want at the 4000 RPM column. If you plan on going straight SD, keep on truckin! The higher the RPM’s get, the tougher it’s going to be to get all the cells in the column. It’s okay if you miss a few (even a bunch) because we can always hand smooth later. Also, the most important cells to hit in these higher RPM’s are going to be the WOT ones. The more correct we can get them, the easier it is going to be to tune the PE table (if going SD), so try to hit them all if you can.
If you are good, you can hit all these cells often enough to get a good average STFT. You can tell that you’ve found the average STFT for a cell (or close to it) when you “pulse” through it and the STFT value doesn’t change anymore. Just keep at it until you get a good average of as many cells as you can. Now, save the log, and similar to before, we are going to take our STFT histogram and “Paste Special – Add) it into the VE table. Save the table, flash the PCM, and do another logging run using the same procedures as in the previous paragraph. Now your STFT’s should be very close to zero. This time, we’re going to “Paste Special – Multiply by % - Half” the STFT histogram into the VE table. Hand smooth any large spikes or dips. Save the table and flash the PCM.
Now we can log again just to verify where we’re at. If you are happy with your STFT’s (they should all be within a couple points of 0 now) down low, you can skip spinning up to the high RPM’s if you want. You could also keep logging and applying your STFT’s into the VE table as many times as you want, but you probably won’t be able to improve your VE table very much more (assuming your STFT’s are very close to 0. If not, wash, rinse and repeat.). Now we get to spend some quality time with the 3-D graph of the VE table. At this point, there should not be any big peaks or valleys. Hand smooth only for cells in which you didn’t log any data, so that they correspond with the logged cells around them. Personally, I don’t use polynomial smoothing at all. It modifies the VE values enough so that it throws my STFT’s off significantly. That and my VE table is pretty smooth already between the application of my STFT’s and hand smoothing. Generally, it’s okay if the VE table is a little choppy, and long as it doesn’t look like the Rockies and you aren’t experiencing any burst knock.
Now that your VE table is so pretty and correct, go back and re-enable PE mode by setting the PE Enable MAP value back to 15. Also switch LTFT Enable back to “ON”. Flash your PCM. Drive around for a few days or a week, and re-log to see where your LTFT’s ended up. They should all now be within the +/- 5 standard. Congratulations!
Now things get quite a bit easier, because we no longer have to wait for LTFT’s to be learned. First off, open the editor and go to General>Fuel Control>Open & Closed Loop, and set LTFT enable to “OFF”. Then go to General>Fuel Control>Power Enrich. Look for the MAP field under the “PE Enable” heading, and set it to 640 (This will disable PE mode. We don’t want it interfering with our next step). Save these parameters and load it onto your PCM. Now we get to do some more logging.
Method here becomes very important. We want to start out by getting the vehicle up to operating temp, like always. Try to find a long stretch of road with no stops. A high speed limit here also helps. Start the STFT histogram as you’ll be referencing it quite a lot while you’re driving, and start logging. Get into third gear (for an M6, if you have an A4 you may have to experiment to find a gear that works well for the following procedure), and level the RPM’s off at about 1200. Now, we’re going to “pulse” the gas pedal, constantly going from 0 – 100% TPS (this is why we disable PE mode) at a steady rate. This can be a bit tricky, but the object is to hit every MAP cell for the 1200 RPM column from off-idle to WOT. You should be able to cycle through the column a couple times before the engine falls into the 1600 RPM column. Continue doing this for all subsequent RPM columns. If you plan on using your MAF again after tuning your VE table, you can stop if you want at the 4000 RPM column. If you plan on going straight SD, keep on truckin! The higher the RPM’s get, the tougher it’s going to be to get all the cells in the column. It’s okay if you miss a few (even a bunch) because we can always hand smooth later. Also, the most important cells to hit in these higher RPM’s are going to be the WOT ones. The more correct we can get them, the easier it is going to be to tune the PE table (if going SD), so try to hit them all if you can.
If you are good, you can hit all these cells often enough to get a good average STFT. You can tell that you’ve found the average STFT for a cell (or close to it) when you “pulse” through it and the STFT value doesn’t change anymore. Just keep at it until you get a good average of as many cells as you can. Now, save the log, and similar to before, we are going to take our STFT histogram and “Paste Special – Add) it into the VE table. Save the table, flash the PCM, and do another logging run using the same procedures as in the previous paragraph. Now your STFT’s should be very close to zero. This time, we’re going to “Paste Special – Multiply by % - Half” the STFT histogram into the VE table. Hand smooth any large spikes or dips. Save the table and flash the PCM.
Now we can log again just to verify where we’re at. If you are happy with your STFT’s (they should all be within a couple points of 0 now) down low, you can skip spinning up to the high RPM’s if you want. You could also keep logging and applying your STFT’s into the VE table as many times as you want, but you probably won’t be able to improve your VE table very much more (assuming your STFT’s are very close to 0. If not, wash, rinse and repeat.). Now we get to spend some quality time with the 3-D graph of the VE table. At this point, there should not be any big peaks or valleys. Hand smooth only for cells in which you didn’t log any data, so that they correspond with the logged cells around them. Personally, I don’t use polynomial smoothing at all. It modifies the VE values enough so that it throws my STFT’s off significantly. That and my VE table is pretty smooth already between the application of my STFT’s and hand smoothing. Generally, it’s okay if the VE table is a little choppy, and long as it doesn’t look like the Rockies and you aren’t experiencing any burst knock.
Now that your VE table is so pretty and correct, go back and re-enable PE mode by setting the PE Enable MAP value back to 15. Also switch LTFT Enable back to “ON”. Flash your PCM. Drive around for a few days or a week, and re-log to see where your LTFT’s ended up. They should all now be within the +/- 5 standard. Congratulations!
05-22-2005, 10:20 AM
#3
Originally Posted by Pro Mouse
Do I then do the Same proceedures for the STFT's as I did with the LTFT's?Do I stay in SD Mode for STLT's?I dont mean to jump the gun here,But IF I do indeed get my LTFT's dialed in today,I want to get this Finished asap.
Thanks!
Thanks!
05-22-2005, 06:46 PM
#6
Originally Posted by soundengineer
Tuning With STFT’s Alone
Now things get quite a bit easier, because we no longer have to wait for LTFT’s to be learned. First off, open the editor and go to General>Fuel Control>Open & Closed Loop, and set LTFT enable to “OFF”. Then go to General>Fuel Control>Power Enrich. Look for the MAP field under the “PE Enable” heading, and set it to 640 (This will disable PE mode. We don’t want it interfering with our next step). Save these parameters and load it onto your PCM. Now we get to do some more logging.
Method here becomes very important. We want to start out by getting the vehicle up to operating temp, like always. Try to find a long stretch of road with no stops. A high speed limit here also helps. Start the STFT histogram as you’ll be referencing it quite a lot while you’re driving, and start logging. Get into third gear (for an M6, if you have an A4 you may have to experiment to find a gear that works well for the following procedure), and level the RPM’s off at about 1200. Now, we’re going to “pulse” the gas pedal, constantly going from 0 – 100% TPS (this is why we disable PE mode) at a steady rate. This can be a bit tricky, but the object is to hit every MAP cell for the 1200 RPM column from off-idle to WOT. You should be able to cycle through the column a couple times before the engine falls into the 1600 RPM column. Continue doing this for all subsequent RPM columns. If you plan on using your MAF again after tuning your VE table, you can stop if you want at the 4000 RPM column. If you plan on going straight SD, keep on truckin! The higher the RPM’s get, the tougher it’s going to be to get all the cells in the column. It’s okay if you miss a few (even a bunch) because we can always hand smooth later. Also, the most important cells to hit in these higher RPM’s are going to be the WOT ones. The more correct we can get them, the easier it is going to be to tune the PE table (if going SD), so try to hit them all if you can.
If you are good, you can hit all these cells often enough to get a good average STFT. You can tell that you’ve found the average STFT for a cell (or close to it) when you “pulse” through it and the STFT value doesn’t change anymore. Just keep at it until you get a good average of as many cells as you can. Now, save the log, and similar to before, we are going to take our STFT histogram and “Paste Special – Add) it into the VE table. Save the table, flash the PCM, and do another logging run using the same procedures as in the previous paragraph. Now your STFT’s should be very close to zero. This time, we’re going to “Paste Special – Multiply by % - Half” the STFT histogram into the VE table. Hand smooth any large spikes or dips. Save the table and flash the PCM.
Now we can log again just to verify where we’re at. If you are happy with your STFT’s (they should all be within a couple points of 0 now) down low, you can skip spinning up to the high RPM’s if you want. You could also keep logging and applying your STFT’s into the VE table as many times as you want, but you probably won’t be able to improve your VE table very much more (assuming your STFT’s are very close to 0. If not, wash, rinse and repeat.). Now we get to spend some quality time with the 3-D graph of the VE table. At this point, there should not be any big peaks or valleys. Hand smooth only for cells in which you didn’t log any data, so that they correspond with the logged cells around them. Personally, I don’t use polynomial smoothing at all. It modifies the VE values enough so that it throws my STFT’s off significantly. That and my VE table is pretty smooth already between the application of my STFT’s and hand smoothing. Generally, it’s okay if the VE table is a little choppy, and long as it doesn’t look like the Rockies and you aren’t experiencing any burst knock.
Now that your VE table is so pretty and correct, go back and re-enable PE mode by setting the PE Enable MAP value back to 15. Also switch LTFT Enable back to “ON”. Flash your PCM. Drive around for a few days or a week, and re-log to see where your LTFT’s ended up. They should all now be within the +/- 5 standard. Congratulations!
Now things get quite a bit easier, because we no longer have to wait for LTFT’s to be learned. First off, open the editor and go to General>Fuel Control>Open & Closed Loop, and set LTFT enable to “OFF”. Then go to General>Fuel Control>Power Enrich. Look for the MAP field under the “PE Enable” heading, and set it to 640 (This will disable PE mode. We don’t want it interfering with our next step). Save these parameters and load it onto your PCM. Now we get to do some more logging.
Method here becomes very important. We want to start out by getting the vehicle up to operating temp, like always. Try to find a long stretch of road with no stops. A high speed limit here also helps. Start the STFT histogram as you’ll be referencing it quite a lot while you’re driving, and start logging. Get into third gear (for an M6, if you have an A4 you may have to experiment to find a gear that works well for the following procedure), and level the RPM’s off at about 1200. Now, we’re going to “pulse” the gas pedal, constantly going from 0 – 100% TPS (this is why we disable PE mode) at a steady rate. This can be a bit tricky, but the object is to hit every MAP cell for the 1200 RPM column from off-idle to WOT. You should be able to cycle through the column a couple times before the engine falls into the 1600 RPM column. Continue doing this for all subsequent RPM columns. If you plan on using your MAF again after tuning your VE table, you can stop if you want at the 4000 RPM column. If you plan on going straight SD, keep on truckin! The higher the RPM’s get, the tougher it’s going to be to get all the cells in the column. It’s okay if you miss a few (even a bunch) because we can always hand smooth later. Also, the most important cells to hit in these higher RPM’s are going to be the WOT ones. The more correct we can get them, the easier it is going to be to tune the PE table (if going SD), so try to hit them all if you can.
If you are good, you can hit all these cells often enough to get a good average STFT. You can tell that you’ve found the average STFT for a cell (or close to it) when you “pulse” through it and the STFT value doesn’t change anymore. Just keep at it until you get a good average of as many cells as you can. Now, save the log, and similar to before, we are going to take our STFT histogram and “Paste Special – Add) it into the VE table. Save the table, flash the PCM, and do another logging run using the same procedures as in the previous paragraph. Now your STFT’s should be very close to zero. This time, we’re going to “Paste Special – Multiply by % - Half” the STFT histogram into the VE table. Hand smooth any large spikes or dips. Save the table and flash the PCM.
Now we can log again just to verify where we’re at. If you are happy with your STFT’s (they should all be within a couple points of 0 now) down low, you can skip spinning up to the high RPM’s if you want. You could also keep logging and applying your STFT’s into the VE table as many times as you want, but you probably won’t be able to improve your VE table very much more (assuming your STFT’s are very close to 0. If not, wash, rinse and repeat.). Now we get to spend some quality time with the 3-D graph of the VE table. At this point, there should not be any big peaks or valleys. Hand smooth only for cells in which you didn’t log any data, so that they correspond with the logged cells around them. Personally, I don’t use polynomial smoothing at all. It modifies the VE values enough so that it throws my STFT’s off significantly. That and my VE table is pretty smooth already between the application of my STFT’s and hand smoothing. Generally, it’s okay if the VE table is a little choppy, and long as it doesn’t look like the Rockies and you aren’t experiencing any burst knock.
Now that your VE table is so pretty and correct, go back and re-enable PE mode by setting the PE Enable MAP value back to 15. Also switch LTFT Enable back to “ON”. Flash your PCM. Drive around for a few days or a week, and re-log to see where your LTFT’s ended up. They should all now be within the +/- 5 standard. Congratulations!
05-22-2005, 09:09 PM
#7
yes,.....
start at like 10 MPH in 6th gear to do the 400 and 800 rpm ranges...(also a good way to get LTFT's in those cells)
then just find some lonely road where there are surre to be no cops and nobody to annoy...and start driving...
hit as many cells as possible...several times over...
I went on a long highway drive to visit family....and just made sure I hit every rpm range like 12 times...
but you can do it with as little as 4 or 5 pulses...
I had about 2 hours worth of logging going there..and the same heading home...so I had plenty of time to get mine all correct
start at like 10 MPH in 6th gear to do the 400 and 800 rpm ranges...(also a good way to get LTFT's in those cells)
then just find some lonely road where there are surre to be no cops and nobody to annoy...and start driving...
hit as many cells as possible...several times over...
I went on a long highway drive to visit family....and just made sure I hit every rpm range like 12 times...
but you can do it with as little as 4 or 5 pulses...
I had about 2 hours worth of logging going there..and the same heading home...so I had plenty of time to get mine all correct
Rainy here now.So start out slow and floor it 4-5 times and se what I covered?I am an A4 car so you are right it's going to be trickier for me....