Anyone still messing around with their BS3? I'm getting into it now and have learned/relearned a TON in the last few days.
Driveability Tune For A Bs3
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Since it is winter time now, I am using that as a great excuse for why my car is sitting doing nothing.... How are you learning it? I absolutely 100% must get my car back on the road in the spring on pump gas tune and much less boost.
That poor poor 93gt. I predict that Captnsave-a-ho will visit you in the spring and help get your car driving on the road again. It needs it badly! IIRC, it's been 3 years since drivin, 2 years since started right? I will personally bring you 5 gallons of E98 and a couple gallons of E0 and we'll get your car to Advanced Auto Fab or some place else you may like.
Trial and error, mostly.
Heavy usage of the logging/replay functions and just playing with the numbers even though I don't know exactly what everything does. I mean, I read the manual thoroughly, which turned up a couple of things I didn't realize. For example, the bottom left cell in your VE table, no matter what the rpm or MAP specified there, is your cold idle timing. There's just no way to know that based on the information in the table, and it doesn't come up in the fuel table part of the manual. I found it in a section about setting idle up for the first time.
I'm just not as worried as I used to be that I'll do something stupid. As long as I keep the fuel mixture in a safe spot (11.5-ish) under boost, . The timing map was my biggest problem before, because you just can't do it right without measuring power output or knowing from experience where it should be. HPP gave me that, and I've seen what the car wants on the dyno a few times. So now, all that's left is getting fuel right. The O2 corrections in closed loop are an awesome tuning aid, and that's loggable.
Transient fuel was a bear for me, and it's still not quite right when it first starts up. After warm, though, it seems great. There are a lot of transient adjustments and it's hard to know how adjusting one will affect others. That was overwhelming when I didn't have idle and cruise in good shape. But, now that they are at least in the ballpark, I feel motivated to keep tweaking, because I have a baseline I can go back to.
Come back to California, and we'll get that tune fixed. Go buy an IAC. It's important for cold idle and preventing stalls.
Heavy usage of the logging/replay functions and just playing with the numbers even though I don't know exactly what everything does. I mean, I read the manual thoroughly, which turned up a couple of things I didn't realize. For example, the bottom left cell in your VE table, no matter what the rpm or MAP specified there, is your cold idle timing. There's just no way to know that based on the information in the table, and it doesn't come up in the fuel table part of the manual. I found it in a section about setting idle up for the first time.
I'm just not as worried as I used to be that I'll do something stupid. As long as I keep the fuel mixture in a safe spot (11.5-ish) under boost, . The timing map was my biggest problem before, because you just can't do it right without measuring power output or knowing from experience where it should be. HPP gave me that, and I've seen what the car wants on the dyno a few times. So now, all that's left is getting fuel right. The O2 corrections in closed loop are an awesome tuning aid, and that's loggable.
Transient fuel was a bear for me, and it's still not quite right when it first starts up. After warm, though, it seems great. There are a lot of transient adjustments and it's hard to know how adjusting one will affect others. That was overwhelming when I didn't have idle and cruise in good shape. But, now that they are at least in the ballpark, I feel motivated to keep tweaking, because I have a baseline I can go back to.
Come back to California, and we'll get that tune fixed. Go buy an IAC. It's important for cold idle and preventing stalls.
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Right on! Why didn't you pick me up?!I drove it a little this yearvery little.
I'm not sure that anyone here can help me, but I might as well post up some stuff that might help others in the future as I work through my issues.
So, this is what I'm currently trying to figure out:
That "desired RPM table" is your warm up table to help with cold idle. I've been dinking around with the cold idle trying to get it working right. In this snap shot, the car was surging a bit, but I have been able to get a smooth cold idle at around 900 RPM. What's weird is that I don't think the IAC is working. So, it won't bring the RPM up to what's desired. The "max TPS % for idle" should be 2-3% higher than idle TPS. Here, after adjusting the screw to set warm idle, my idle TPS is 3.0% and I need to adjust the Max TPS for idle up to at least 5%. I understand that if these numbers aren't set correctly, then none of the idle tables will work. This may be the problem I'm having with the IAC, but I don't think so, because it wasn't working when the idle TPS was only 2%. Tomorrow, I'll try bumping it up to 6% to see if that makes any difference.
Another peculiarity to me: the bubble in the idle spark table should be on the far left at an RPM Delta of -256 or less, where it would advance the timing by 11 degrees and try to bring it back up. For whatever reason, it's actually on the far right, where it would normally retard timing, and I'm not really sure why. However, cold idle timing (bottom-left most cell in the main spark table) is set at 27 degrees, and the "Idle spark" doesn't seem to be affecting that. I haven't noticed if the idle spark table works correctly once the car warms up, because it idles right where it should, and the RPM Delta goes to 0. I might play around with the throttle blade adjustment screw later to test it when I have less pressing concerns.
So, this is what I'm currently trying to figure out:
That "desired RPM table" is your warm up table to help with cold idle. I've been dinking around with the cold idle trying to get it working right. In this snap shot, the car was surging a bit, but I have been able to get a smooth cold idle at around 900 RPM. What's weird is that I don't think the IAC is working. So, it won't bring the RPM up to what's desired. The "max TPS % for idle" should be 2-3% higher than idle TPS. Here, after adjusting the screw to set warm idle, my idle TPS is 3.0% and I need to adjust the Max TPS for idle up to at least 5%. I understand that if these numbers aren't set correctly, then none of the idle tables will work. This may be the problem I'm having with the IAC, but I don't think so, because it wasn't working when the idle TPS was only 2%. Tomorrow, I'll try bumping it up to 6% to see if that makes any difference.
Another peculiarity to me: the bubble in the idle spark table should be on the far left at an RPM Delta of -256 or less, where it would advance the timing by 11 degrees and try to bring it back up. For whatever reason, it's actually on the far right, where it would normally retard timing, and I'm not really sure why. However, cold idle timing (bottom-left most cell in the main spark table) is set at 27 degrees, and the "Idle spark" doesn't seem to be affecting that. I haven't noticed if the idle spark table works correctly once the car warms up, because it idles right where it should, and the RPM Delta goes to 0. I might play around with the throttle blade adjustment screw later to test it when I have less pressing concerns.
This looks very similar to tuner studio.
Are you sure you don't need to denote an - before the numbers in the positive rpm delta range? The way you have it set it looks like you are increasing timing there.
Another oddity the delta rpm should follow the commanded rpm/clt temp so at 900rpm you should have a -500rpm delta and increase timing to bring idle speed up.
Imho your closed loop idle activation settings may be incorrect this will cause the system to run in warm-up mode (table driven idle no automatic correction)
Can you post up those tables? Maybe I can help there, also what Hz are you commanding the idle valve at? Bosch valves like ours run best at 98-150hz above this they get much less accurate.
Your valve polarity may also be wrong, should be a setting for this it may be commanding it to open but driving it closed.
Are you sure you don't need to denote an - before the numbers in the positive rpm delta range? The way you have it set it looks like you are increasing timing there.
Another oddity the delta rpm should follow the commanded rpm/clt temp so at 900rpm you should have a -500rpm delta and increase timing to bring idle speed up.
Imho your closed loop idle activation settings may be incorrect this will cause the system to run in warm-up mode (table driven idle no automatic correction)
Can you post up those tables? Maybe I can help there, also what Hz are you commanding the idle valve at? Bosch valves like ours run best at 98-150hz above this they get much less accurate.
Your valve polarity may also be wrong, should be a setting for this it may be commanding it to open but driving it closed.
I am sure. I have been over and over this table due to this discrepancy. Like you, I do not agree with the say he programmed it, and I would prefer to see "-" signs for the timing on the right side of the table. However, the instruction manual is explicit in the fact that the table will retard timing on the right side and a negative sign is not necessary. In fact, I tried putting one in just to see if I could force a timing adjustment and it would not accept a negative.
I agree. Totally confused on why it's doing this. However, as mentioned, it is not actually having an impact on timing. My main spark table calls for 27* and in the dashboard at the bottom of the pic, you can see that's exactly what it's getting.
That could be true. I believe the closed loop activation is commanded above 1200 and off below 1100, IIRC. I'll check it out when I get home, today. That would be below the commanded/desired idle RPM. I think I'd prefer not to run closed loop at idle, since I'm paying so much attention to setting the tune there manually.
I'm a little confused about your question. I do not recall a Hz setting in any of the tables. To what Bosch valves are you referring? Are we talking about the IAC?
The closed loop settings I am referring to are for idle control, not ego. You want the idle to be closed loop or none of the aforementioned table will do squat.
You may not have a Hz selection option for the idle valve, i do. I have not used bs3 so I am using terms and settings I am accustomed to.
You may not have a Hz selection option for the idle valve, i do. I have not used bs3 so I am using terms and settings I am accustomed to.
Hmm... Ok. I'll take a few screen shots with all of the idle tables so you can see what I'm working with. I don't think there's a separate closed loop setting for idle. I assume ego is exhaust gas oxygen fuel trimming, but I think that's the only closed loop setting I have. That's still a good idea to play with and might have something to do with this situation.
Sorry. It's not going to be tonight, as I promised. I am behind in my studies, and there's a calculus test tomorrow.
Have you seen the new BigComm that come out last year? It looks pretty promising
http://bigcommpro.com/software-5/bigcomm-pro
http://bigcommpro.com/software-5/bigcomm-pro
Yes I did. I think it looks pretty sweet, and I may buy it. I love the idea of a long term log of collected data on each cell.
Right now, however, I'm actually enjoying figuring things out on my own, and the car, oil burning issue aside, is running very nicely.
I might add that in my upgrade to SR2, BigStuff apparently disabled my IAC and all idle settings. I'm going to have a chat with them about it, because I was not in any way made aware of this consequence. Apparently, the SR2 upgrade, which allows me to use an accelerometer and other functions, is so racecar-ish that they didn't expect people using it to want street/idle manners.
I actually believe I've tuned around this issue for the most part as idle has never been better. However, I'm concerned that when I get the a/c issue figured out that I may have trouble running it at idle without some form of RPM compensation.
Right now, however, I'm actually enjoying figuring things out on my own, and the car, oil burning issue aside, is running very nicely.
I might add that in my upgrade to SR2, BigStuff apparently disabled my IAC and all idle settings. I'm going to have a chat with them about it, because I was not in any way made aware of this consequence. Apparently, the SR2 upgrade, which allows me to use an accelerometer and other functions, is so racecar-ish that they didn't expect people using it to want street/idle manners.
I actually believe I've tuned around this issue for the most part as idle has never been better. However, I'm concerned that when I get the a/c issue figured out that I may have trouble running it at idle without some form of RPM compensation.
Hopefully, that helps, and I'll pass along updates whenever you like. It would be great to work with someone on tuning and learning the quirks of the BS3.
Thank you Chris, I appreciate it.
I plan on punishing my drag radials this spring.
I plan on punishing my drag radials this spring.
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