Base Running Air Tuning Help
06-03-2010, 12:17 AM
#1
Base Running Air Tuning Help I am new to tuning and hp tuners as well. I have read about everything I could and a few things are still not making sense to me
The car was tuned at a local shop that is very reputable. I was only having some minor idle surging and some other minor drive ability issues. I wanted to learn how to tune so figured this is as good a time as any. Car has 6.0L 9.5:1 CR with 226/222 116 LSA cam, 1.85 rockers and SLP MAF.
I am assuming that the tuner did a good job on the MAF scaling and VE portion of the tune.
I started by working on the base running air table. I tried to use some of the idle configs that other users have suggested. I can get the histograms to plot data but not in the right ECT fields. Any ideas?
Also when I average idle airflow desired values to update the base running airflow table I am getting numbers in the 5's when at operating temp which are way less than the stock table. I tried running them this way and the car would barely idle and would stall out if put into gear. STIT's were around 1.3 to 1.5. I made a 1.3 correction in the base running air table hoping to lower the STIT and it got very close to the same STIT's after a few minutes. It was acting as if I did not make a change.
Currently I have numbers I came up with from the P\N base airflow and In Gear airflow which almost matches the MAF readings and it seems to be running pretty well. STIT's are around -1.3. I made a -1.3 correction to table and got almost the same STIT again after a few minutes.
Is there something I am doing wrong with this correction? I added 4 deg timing and that seemed to help the most. It liked 6 deg a little more but the STIT started to go down lower. For such a small cam I am surprised it liked the timing.
Any ideas or pointing me in a different directions would be greatly appreciated. Thanks for your time.
The car was tuned at a local shop that is very reputable. I was only having some minor idle surging and some other minor drive ability issues. I wanted to learn how to tune so figured this is as good a time as any. Car has 6.0L 9.5:1 CR with 226/222 116 LSA cam, 1.85 rockers and SLP MAF.
I am assuming that the tuner did a good job on the MAF scaling and VE portion of the tune.
I started by working on the base running air table. I tried to use some of the idle configs that other users have suggested. I can get the histograms to plot data but not in the right ECT fields. Any ideas?
Also when I average idle airflow desired values to update the base running airflow table I am getting numbers in the 5's when at operating temp which are way less than the stock table. I tried running them this way and the car would barely idle and would stall out if put into gear. STIT's were around 1.3 to 1.5. I made a 1.3 correction in the base running air table hoping to lower the STIT and it got very close to the same STIT's after a few minutes. It was acting as if I did not make a change.
Currently I have numbers I came up with from the P\N base airflow and In Gear airflow which almost matches the MAF readings and it seems to be running pretty well. STIT's are around -1.3. I made a -1.3 correction to table and got almost the same STIT again after a few minutes.
Is there something I am doing wrong with this correction? I added 4 deg timing and that seemed to help the most. It liked 6 deg a little more but the STIT started to go down lower. For such a small cam I am surprised it liked the timing.
Any ideas or pointing me in a different directions would be greatly appreciated. Thanks for your time.
06-03-2010, 12:36 AM
#3
You've got 10+ degrees too much idle timing. Put it back to stock then run the config again. Also keep a check on your AFR. Changing the timing will affect your AFR and make your airflow tables be slightly off.
Log the timing advance along with everything else.
Edit: Actually all your airflow tables are stock. That's probably most of your problems. Your tuner ripped you off. Great way to blow up a turbo car.
Log the timing advance along with everything else.
Edit: Actually all your airflow tables are stock. That's probably most of your problems. Your tuner ripped you off. Great way to blow up a turbo car.
Last edited by JonCR96Z; 06-03-2010 at 12:47 AM.
06-03-2010, 10:19 AM
#4
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You've got 10+ degrees too much idle timing. Put it back to stock then run the config again. Also keep a check on your AFR. Changing the timing will affect your AFR and make your airflow tables be slightly off.
Log the timing advance along with everything else.
Edit: Actually all your airflow tables are stock. That's probably most of your problems. Your tuner ripped you off. Great way to blow up a turbo car.
Log the timing advance along with everything else.
Edit: Actually all your airflow tables are stock. That's probably most of your problems. Your tuner ripped you off. Great way to blow up a turbo car.
06-03-2010, 10:31 AM
#5
Why would you leave the MAF table mostly stock? That is the main airflow table that tells the PCM how much air is entering the engine. And just because GM put the MAF sensors on a flow bench and got the transfer function in the tunes with it doesnt mean that your different air pump (aka engine) pumps air the same way as a flow bench! That table needs to be calibrated with the setup to accurately calculate airflow so the PCM can supply the correct amount of fuel!
06-03-2010, 08:39 PM
#7
Thanks for the info and reply to both HP tuners and here. On HP tuners I was more after why the histo would not plot correctly. Still dont have an answer for that. I don't have the stock tune to compare the timing to so I put it back to where I started. I will download a stock tune and compare again. If the car is idling beter now is there any concern running it with more base running air than called for by the idle desired air? STIT is around -1.3. Like I commented the STIT did not really move when I made a correction to the table to compensate for it. What is going on with that? Also what is the concern with the MAF tables not being scaled correctly? As long as all the tables reference it correctly won't that give the same results?
Sorry for all the beginer questions. Hard to get answers like this reading a book and posts.
Thanks for everyones time.
Sorry for all the beginer questions. Hard to get answers like this reading a book and posts.
Thanks for everyones time.
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06-03-2010, 09:59 PM
#8
Thanks for the info and reply to both HP tuners and here. On HP tuners I was more after why the histo would not plot correctly. Still dont have an answer for that. I don't have the stock tune to compare the timing to so I put it back to where I started. I will download a stock tune and compare again. If the car is idling beter now is there any concern running it with more base running air than called for by the idle desired air? STIT is around -1.3. Like I commented the STIT did not really move when I made a correction to the table to compensate for it. What is going on with that? Also what is the concern with the MAF tables not being scaled correctly? As long as all the tables reference it correctly won't that give the same results?
Sorry for all the beginer questions. Hard to get answers like this reading a book and posts.
Thanks for everyones time.
Sorry for all the beginer questions. Hard to get answers like this reading a book and posts.
Thanks for everyones time.
The config showed up perfect on mine. Not sure what your problem is there.
The idle airflow table is just a base for where the PCM will start correcting. Once adaptive idle (STIT and LTIT) comes into play it's gonna adjust itself, but the times you don't have adaptive idle it's not gonna like it. Which explains your stalling while putting it into gear. On an automatic it's easier to work around otherwise. The PCM also uses timing to make corrections, which is why I said to log timing in that config as well. If you changed the RAF and the idle trims didn't change, then the timing probably did.
Right now you have too much timing and not enough airflow. There are few LS1s (regardless of mods) that won't idle perfectly with 20 or less degrees of timing. It's actually better with less as you have more cushion between the base timing and the MBT value that the PCM can adjust for to help stabilize a rough idle.
The MAF table (and VE) is how the car knows how much fuel to add. If it's wrong, the AFR will be wrong. And it's not easy to get a car running correctly if the AFR is wrong. Correcting these to tables is what I call "tuning". To me, your PCM isn't 'tuned', it's just half-assed.
3 things go into making an engine run. Air, fuel and spark. If one or two of those are wrong you're gonna have trouble. Sometimes you might be able to live with it and sometimes not, but it's still wrong.
06-03-2010, 10:34 PM
#9
With the config and the log file I posted you were getting data in the correct fields that matched what you were seeing on the table view? Specifically the airflow data showing up for the right ECT value? What version of software are you running?
The configs I was using before had timing. I will take a look at them to see if the timing changed.
Thanks for the answers to all my questions.
The configs I was using before had timing. I will take a look at them to see if the timing changed.
Thanks for the answers to all my questions.
06-04-2010, 10:21 PM
#11
Thank for the help. I loaded the software on another computer and it worked just fine. Even after reloading it on the same computer it is having the same problem as before. Is there some setting that would have gotten changed or something that a reinstall would not fix?. I will play with it some more tonight to see if I can get it to work.
06-04-2010, 11:11 PM
#12
It has to be something in the config itself. A reload wouldn't change those things unless you completely uninstalled it first.
Can you post a screen shot of what it's doing and another of the histogram setup. Or try just making a new histogram of the same thing and see if that one works.
Can you post a screen shot of what it's doing and another of the histogram setup. Or try just making a new histogram of the same thing and see if that one works.
06-04-2010, 11:33 PM
#13
I completely uninstalled everything and manually erased all traces of HP tuners from the computer. I saved all of my config and tune files in another location. After a fresh install and using the same configs and log files it is working perfectly.
Previously I did try making multiple configs and running different log files and no matter what combination I tried I could not get it to plot correctly. It kept putting the air flow numbers in the wrong fields. If the car was started up at 68 deg f it would start plotting in the 25 or 46 deg field and would only fill 5 fields. Really bizarre. I am glad it is working now though. What a pain.
Previously I did try making multiple configs and running different log files and no matter what combination I tried I could not get it to plot correctly. It kept putting the air flow numbers in the wrong fields. If the car was started up at 68 deg f it would start plotting in the 25 or 46 deg field and would only fill 5 fields. Really bizarre. I am glad it is working now though. What a pain.
06-05-2010, 02:02 AM
#14
When you adjust your RAF are you doing it in RTT? or adjusting in the tune flash it and then restart the engine? I've played around with some RTT features on a couple car's and for whatever reason it takes better to adjustments to just log the data, make an adjustment and flash it to the car and then re log and see how it does! Also I would rather the STIT be negative than positive! When the Idle trim's are having to add airflow then on the rpm blips and coast down's will be a really low idle unless you have your follower and cracker table cranked up! Just a few more pieces of info to add to that.
06-05-2010, 07:48 AM
#15
I have been logging and then flashing separately. Thanks for the suggestion on having the STIT on the negative side. Currently that is where it is at. I will put timing back to stock as suggested and then re run the logs for idle and see what happens. Thanks.
06-06-2010, 10:03 PM
#17
I took a quick look VE and MAF cals and they don't appear to be causing any issues for idle. I will be going SD towards the end of summer and will cal everything then.
Was able to get the base running airflow table updated for park and drive. Idles well and does not stall from from quick throttle blip back to idle. In drive with light brake applied but still rolling it has a slight surge. It seems to start surging once the idle advance goes to zero. I assume it stops correcting once it senses it is moving. The question is what should I try adjust to help it correct better for idle once its moving?
Was able to get the base running airflow table updated for park and drive. Idles well and does not stall from from quick throttle blip back to idle. In drive with light brake applied but still rolling it has a slight surge. It seems to start surging once the idle advance goes to zero. I assume it stops correcting once it senses it is moving. The question is what should I try adjust to help it correct better for idle once its moving?
06-06-2010, 10:13 PM
#19
I took a quick look VE and MAF cals and they don't appear to be causing any issues for idle. I will be going SD towards the end of summer and will cal everything then.
Was able to get the base running airflow table updated for park and drive. Idles well and does not stall from from quick throttle blip back to idle. In drive with light brake applied but still rolling it has a slight surge. It seems to start surging once the idle advance goes to zero. I assume it stops correcting once it senses it is moving. The question is what should I try adjust to help it correct better for idle once its moving?
Was able to get the base running airflow table updated for park and drive. Idles well and does not stall from from quick throttle blip back to idle. In drive with light brake applied but still rolling it has a slight surge. It seems to start surging once the idle advance goes to zero. I assume it stops correcting once it senses it is moving. The question is what should I try adjust to help it correct better for idle once its moving?
06-06-2010, 10:28 PM
#20
Quick reply. Thanks again for your time.
AFR was 14.5 to 14.9. I have AFR in the log file. HP tuners sees the AFR a little higher than the actual reading. About .3 to .4 higher.
I did lower the compression to 9.5. How will that play into this? Can I use the RTT in the scanner to lower the timing? How much should I try?
Also when I see the idle advance timing not adjusting any more once moving is that normal?
AFR was 14.5 to 14.9. I have AFR in the log file. HP tuners sees the AFR a little higher than the actual reading. About .3 to .4 higher.
I did lower the compression to 9.5. How will that play into this? Can I use the RTT in the scanner to lower the timing? How much should I try?
Also when I see the idle advance timing not adjusting any more once moving is that normal?