E38 VVE Setup Guide

[swingtan]

Hi All,

a little while ago I was taking to a couple of other tuners here in Australia about setting up to do your first VVE adjustments. While I know that those who have been working with EFILive for a few years would have managed to work things out fairly well, us "newbies" ( so to speak ), have a pretty steep learning curve. So after talking a bit I decided to put together a quick quick to help the new comers and maybe a few of the more experienced as well.

Please note that this is aimed at the Holden range of vehicles with the E38 controller, but should work fine for the G8 over in the US. It's been looked over by a couple of guys and should be fairly correct, but if any one finds any discrepancies, let me know and I'll update as needed. It's certainly not a replacement for the doco supplied by EFILive, it just takes a step by step approach to setting up ready to do the work.

Hope this is helpfull to some.


Simon.

EDIT: I just realised I should have stuck this in the "Tutorial" forum.... Mods please move if needed.


EDIT:

Links to final form:
E38 VVE Setup Guide (http://forum.efilive.com/attachment.php?attachmentid=4354&d=1229048532)
Virtual VE Tutorial (http://forum.efilive.com/attachment.php?attachmentid=8002&d=1274505151)

[joecar]

Simon,

Good job... :cheers:

I moved it to the Tutorial section.

Edit: the EFILive supplied doc mentioned above by Simon is attached see post #51 (it also is included when you install V7.5).

[oztracktuning]

Its a great effort Swingtan, Thanks there are some great ideas in it.
Just a few suggestions for consideration.

Paul has suggested that the best way to go mafless is not 1, 1 approach, it might be better to reverse the highs and the lows. ie. swap the 13500 and the 10. There have been some mystery problems in some cars that are set with 1s.

I also edit DTC Type P0101 P0102 P0103 from B to C (not reported)

Also a tip for Forced induction people beware of a weird effect of burst knock activation mid acceleration not just at throttle tip in.

Also DFCO delay in M6s is set to 0.1s. This may have been a mistake in the stock calibration.

[vxchev8]

Well done Simon - Thanks for taking the time to do the tutorial.

[Stelth]

Good work mate !

[ringram]

Nice good reference for LTFT and STFT stuff, saves me getting the threads out from favourites..

[swingtan]

Thanks for the kind words guys. I know it took me a while to get my head around the VVE adjustments. A couple of guys asked what I'd done and I felt if I put something together it would not only reinforce my own thoughts, but help as many others as possible.



Paul has suggested that the best way to go mafless is not 1, 1 approach, it might be better to reverse the highs and the lows. ie. swap the 13500 and the 10. There have been some mystery problems in some cars that are set with 1s.


I have heard the odd report about this, but didn't experience anything myself with the "all 1's" settings. I have no problems changing it, as long I can understand why. I like to at least know the reasons why things are done before I start telling others what to do ;)




I also edit DTC Type P0101 P0102 P0103 from B to C (not reported)



I take it you mean in "DTC Type" ? I did note on page 4 to turn off the codes in "DTC MIL" ( though I didn't actually say it was in DTC MIL, just to disable the MIL light ). Does setting these to "Not Report" add anything over not logging the DTC in the ECM? I guess if you were staying SD, then you would want these off.



Also DFCO delay in M6s is set to 0.1s. This may have been a mistake in the stock calibration.

I just checked my stock tune ( L76 M6 ) and it is set to 0.5 standard. To make it feel smooth, I think the injector timing is used to extend the time it takes from no DFCO to full DFCO and vice versa.

It looks like I've singled you out Steve, but it's just that you have raised some good points.

Simon.

[Jester]

I take it you mean in "DTC Type" ? I did note on page 4 to turn off the codes in "DTC MIL" ( though I didn't actually say it was in DTC MIL, just to disable the MIL light ). Does setting these to "Not Report" add anything over not logging the DTC in the ECM? I guess if you were staying SD, then you would want these off.


I think Steve meant setting them to 'C' "Non Emissions" in DTC Type.

[swingtan]

Yes, I got that. I did some testing last weekend and setting "DTC Type" to "X: Not reported" is not very helpful. there are 2 possible results from doing this.


If the MAF is still plugged in correctly and functioning, it will still be used for air flow measurements as you have just told the ECM to ignore any MAF failures. So it will continue to use the signal coming from the MAF, even if the test settings say it should have failed.

If the MAF has been disconnected, the car will start and then stall as it will get no fuel. As the PCM has been told to ignore MAF failures and the MAF is disconnected, it will read the air flow as the minimum MAF setting ( in my case 0.55 gm/S ). Given the very small airflow being used, the PCM will simply not inject any fuel and the engine will stall.



So the idea would be to set the following:



If you are planing on going back to using the MAF, the changes should be...


DTC MIL - P0101 = No MIL
DTC MIL - P0102 = No MIL
DTC MIL - P0103 = No MIL

and optionally

DTC Type - P0101 = C: Non Emissions
DTC Type - P0102 = C: Non Emissions
DTC Type - P0103 = C: Non Emissions

All these will need to be returned to stock when the MAF is returned to service.

If you are going to remain MAF-less...



DTC Type - P0101 = C: Non Emissions
DTC Type - P0102 = C: Non Emissions
DTC Type - P0103 = C: Non Emissions

DTC MIL - P0101 = No MIL
DTC MIL - P0102 = No MIL
DTC MIL - P0103 = No MIL

[Jester]

If you are going to remain MAF-less...



DTC Type - P0101 = C: Non Emissions
DTC Type - P0102 = C: Non Emissions
DTC Type - P0103 = C: Non Emissions

DTC MIL - P0101 = No MIL
DTC MIL - P0102 = No MIL
DTC MIL - P0103 = No MIL
Yes thats how mine are set for mafless.

[427]

well done and good read buddy-very informative

Thanks

427

[swingtan]

I have made a small update to the guide to take into account the MAF test settings as mentioned in Oztracks post. Nothing major, I just wanted to make sure that the guide was in line with current best practice....


Simon.

[joecar]

Simon, thanks for updating... :cheers:

[GMPX]

Thanks Simon, we should get that up on the main downloads page (if that is ok with you?)

Cheers,
Ross

[swingtan]

It's certainly OK with me. Are you happy with the PDF file or do you want it in an MS Word format? I have both.

Simon

[GMPX]

PDF is best.

Cheers,
Ross

[swingtan]

OK, you have the latest copy then. :D

[Tordne]

Added under the title "Virtual VE Adjustment Tutorial". Nice work!

[ringram]

When are you collecting your new HSV R8 Tordne? :)

[Tordne]

If all goes well with this Saturday's 6 million dollar Lotto dray, it will be first thing Sunday :)

[GMPX]

If all goes well with this Saturday's 6 million dollar Lotto dray, it will be first thing Sunday :)
I'm waiting to win Lotto too, only problem is I don't enter it :doh:
I also can't justify spending HSV kind of money on something I'd only drive once a week at best (I must be getting old), mind you, I'd happily stare at a new Z06 in the garage any day.

[Tordne]

So my odds are only marginally better than yours then LOL

[joecar]

I'll find an excuse to drive it everyday... :D

[JAY4SPEED]

On page 3 under "Set Command AFRs",

The setting for "Parameter: B0146 Set all cells over 80' to 1.00". Does the 80' refer to the intake valve temp axis or does it refer to the kpa axis? If it is referring to the intake valve temp axis and 80' (or 80*) is that in Celsius or Fahrenheit?

I think the way I read it in my case (I view temps in Imperial) is set every cell over 176*F IVT to 1.00. Would that be correct?

Or could I change the complete table to 1.00 since I won't be using E80 fuel during my Auto VVE process? It refered to using this table after the E80 blending has been calculated. But, I'm sure I don't understand that table correctly.

[swingtan]

b0146 deals with IVT and MAP, so the 80' refers to IVT. And yes, it's Celsius, but you can substitute a value that is just under the normal operating temp of the car. That way you can ensure that this table won't change the commanded AFR's at unexpected times.

The table its self has nothing to do with Ethanol based fuels. It's the final correction factor to the OL fuel calculations after all other calculations have been done ( including the ethanol calculations ). What this table will do is allow you to alter the OL commanded fuel depending on both IVT and MAP. It can be very useful if used correctly.

Simon.

[JAY4SPEED]

I didn't think I understood that table correctly, but I do now. Simon, thanks for taking the time to do the tutorial for us who need step by step help.:)

[alian]

b0146 deals with IVT and MAP, so the 80' refers to IVT. And yes, it's Celsius, but you can substitute a value that is just under the normal operating temp of the car. That way you can ensure that this table won't change the commanded AFR's at unexpected times.

The table its self has nothing to do with Ethanol based fuels. It's the final correction factor to the OL fuel calculations after all other calculations have been done ( including the ethanol calculations ). What this table will do is allow you to alter the OL commanded fuel depending on both IVT and MAP. It can be very useful if used correctly.

Simon.

Nice work Simon, Your work helps so many.
Many Thanks Ian

[gmh308]

Excellent and extremely well thought out document. Very generous of you to share the many hours of work you and your collaborators put into the knowledge to create such and informative source of information for VVE tuning.

Cheers.

[swingtan]

Hi Guys,

Thanks for the kind words and I'm glad a few are finding this useful. I've made another update to the guide......

To help with dialing in the VVE, there is now a section on calibrating the base injector flow rate with IAT. Many will know that as IAT goes up, the AFR's can tend to lean out, so you need to add more fuel to correct for this. the new section describes one method to help set up B1213, resulting in stable AFR's for all IAT's.

Simon.

[gmh308]

Hi Guys,

Thanks for the kind words and I'm glad a few are finding this useful. I've made another update to the guide......

To help with dialing in the VVE, there is now a section on calibrating the base injector flow rate with IAT. Many will know that as IAT goes up, the AFR's can tend to lean out, so you need to add more fuel to correct for this. the new section describes one method to help set up B1213, resulting in stable AFR's for all IAT's.

Simon.

Thanks again Simon. Excellent work.

Interesting that Holden never bothered with B1213. Maybe it just fell outside of the ADR drive cycle and was not a priority for them. Chevy certainly looked at it a little, but not as comprehensive as your work.

Any effect on drivability/throttle response/smoothness?

Cheers.

[swingtan]

I can see a few big issues with not setting up B1213 in a stock tune. Basically, just driving around in summer, the IAT's will get very warm, leaning out the mixture and causing the O2's to tell the ECM to add more fuel. This of course will increase the LTFT amounts to match. But when you give it a bit of a run on the open road and hit PE, the LTFT will add that fuel to the commanded and you'll end up with a very, very rich mixture. Maybe this is one reason why the stock tune end up so rich ( in addition to the VE table and MAF settings ).

The reason for correcting the AFR drift is really more to do with consistency rather than out right performance. For example, imagine you set up the VVE on a cold day with lots of open road driving. Then after setting it all up, a few weeks later the temp rises and you get caught in traffic, heat soaking the intake and the IAT's rise. If you were to "give it a boot full", the mixtures may be significantly leaner than commanded and the timing too great for that mixture. You'll end up with KR where previously you had none.

You could probably tune the KR out with the IAT timing table, but you would then be running much less timing than you could be, if the mixtures were correct.

Simon

[gmh308]

I can see a few big issues with not setting up B1213 in a stock tune. Basically, just driving around in summer, the IAT's will get very warm, leaning out the mixture and causing the O2's to tell the ECM to add more fuel. This of course will increase the LTFT amounts to match. But when you give it a bit of a run on the open road and hit PE, the LTFT will add that fuel to the commanded and you'll end up with a very, very rich mixture. Maybe this is one reason why the stock tune end up so rich ( in addition to the VE table and MAF settings ).

The reason for correcting the AFR drift is really more to do with consistency rather than out right performance. For example, imagine you set up the VVE on a cold day with lots of open road driving. Then after setting it all up, a few weeks later the temp rises and you get caught in traffic, heat soaking the intake and the IAT's rise. If you were to "give it a boot full", the mixtures may be significantly leaner than commanded and the timing too great for that mixture. You'll end up with KR where previously you had none.

You could probably tune the KR out with the IAT timing table, but you would then be running much less timing than you could be, if the mixtures were correct.

Simon

Great reasoning on that one Simon. Getting IAT AFR correct may also be helpful in preventing a tendency for thermal runaway on high temp days as the combustion temp gets higher and higher as the AFR rises, then some KR occurs as you point out and temps continue to rise....

mmmmm.....

[macca_779]

Hi Guys,

Thanks for the kind words and I'm glad a few are finding this useful. I've made another update to the guide......

To help with dialing in the VVE, there is now a section on calibrating the base injector flow rate with IAT. Many will know that as IAT goes up, the AFR's can tend to lean out, so you need to add more fuel to correct for this. the new section describes one method to help set up B1213, resulting in stable AFR's for all IAT's.

Simon.

Interesting method your using for the IAT factor Simon.. I never thought of doing it that way.

My method encompasses getting VE sorted at one temp average. I then perform the Auto VE process at a different time of day but don't apply it rather take an average of all the BEN's and the logged IATs in Excel. The averaged BEN's become the correction factor (invert it if its an E38) and the averaged IAT's are where the factor goes. The rest is linear filled to the original Auto VE average temp. I do it this way because I find heatsoak to give alternate results to actual temperature change which up here can be huge in the space of 24hrs.

[gmh308]

Interesting method your using for the IAT factor Simon.. I never thought of doing it that way.

My method encompasses getting VE sorted at one temp average. I then perform the Auto VE process at a different time of day but don't apply it rather take an average of all the BEN's and the logged IATs in Excel. The averaged BEN's become the correction factor (invert it if its an E38) and the averaged IAT's are where the factor goes. The rest is linear filled to the original Auto VE average temp. I do it this way because I find heatsoak to give alternate results to actual temperature change which up here can be huge in the space of 24hrs.

Macca, what IAT temps do you see up there with heatsoak in the red centre?

[swingtan]

Hey Macca, that's an interesting way of doing it as well. I can see your reasoning and this would work well with the IAT - VE table for the LS1. With the E38, we only really get the INJ vs IAT table to help in this area so have to work with what we have. I had 2 main reasons for doing the correction in this particular way...


By leaving the car idling and allowing the heat soak to increase IAT, nearly all other engine factors that can alter AFR are kept constant. This means any AFR drift is most likely to be caused by IAT and from other things like throttle transitions etc.
It is very quick and very accurate. Using this technique you can dial in the INJ vs IAT table in a single session lasting 30 min.


Of course, it doesn't make up for real world driving data, but is probably not far off in the end result.

Simon.

[macca_779]

Macca, what IAT temps do you see up there with heatsoak in the red centre?

Highest I've seen is in the high 60c range on my car sitting idleing for an extended time. While driving approx 5c above ambient is normal so 50s aren't uncommon. I have an OTRCAI that does return back to realistic values quite quickly. On a Magnacharger LS1 I tuned I would see in the high 90's while WOT. :bad: The crappy water to air intercooler that PWR supplies is the main culprit there though.

[GMPX]

Simon, could you please add in to your tutorial to make sure the MAP units in the VVE tables and the Zone set up tables are the same units, i.e kPa or PSI, not a mix. Probably somewhere on page 7 would be great.

Thanks,
Ross

[swingtan]

Hi Ross,

I've added that in and placed it on P10, where I first describe altering the zone boundaries. I thought that as people would be looking at the table then, it would be a good place to get them to check. I used a different PDF converter which increased the size a little, but it's still well under 1MB.

Download here -
http://download.efilive.com/Tutorials/PDF/Virtual%20VE%20Adjustment%20Tutorial.pdf

Simon

[alian]

Highest I've seen is in the high 60c range on my car sitting idleing for an extended time. While driving approx 5c above ambient is normal so 50s aren't uncommon. I have an OTRCAI that does return back to realistic values quite quickly. On a Magnacharger LS1 I tuned I would see in the high 90's while WOT. :bad: The crappy water to air intercooler that PWR supplies is the main culprit there though.

Macca. Bit new to this but cant you run an intercooler as well as the heat exchange set up they come with.Not sure about the PWR but was looking at a Harrop the other day.
Cheers Ian

[macca_779]

Macca. Bit new to this but cant you run an intercooler as well as the heat exchange set up they come with.Not sure about the PWR but was looking at a Harrop the other day.
Cheers Ian

Don't think so mate. Due to them being a top mount Blower your forced to use a remote water heat exchanger setup. Perhaps a larger front mount and a better pump than the crappy electric one supplied would improve the efficiency but there isn't much I imagine you can do about the blower side of things.
If I was going down the FI route I'd go Turbo's or perhaps a Procharger. The temp increase over ambient is bugger all with a good Air/Air Intercooler

[alian]

Don't think so mate. Due to them being a top mount Blower your forced to use a remote water heat exchanger setup. Perhaps a larger front mount and a better pump than the crappy electric one supplied would improve the efficiency but there isn't much I imagine you can do about the blower side of things.
If I was going down the FI route I'd go Turbo's or perhaps a Procharger. The temp increase over ambient is bugger all with a good Air/Air Intercooler

So cooling the air with an intercooler before it goes into the blowwer wont help at all??

[GMPX]

Hi Ross,

I've added that in and placed it on P10, where I first describe altering the zone boundaries. I thought that as people would be looking at the table then, it would be a good place to get them to check. I used a different PDF converter which increased the size a little, but it's still well under 1MB.

Simon
Thanks Simon, I've uploaded this newer version to the downloads section on the website.

Cheers,
Ross

[macca_779]

So cooling the air with an intercooler before it goes into the blowwer wont help at all??

Bugger all mate. Unless you perhaps cool it with dry ice.

[alian]

Bugger all mate. Unless you perhaps cool it with dry ice.

Thanks 4 that Macca, Did a bit more looking:doh2:
Cheers Ian

[shane]

First of all great work guys this tutorial is a great help.
Where do you find the e38 ben map?Is it a preconfigured map or do i have to write it up?.If i have to make it do you use the normal kpa/rpm ben factor or something different. How do you apply the ben factors to the vve table .You say not like the ls1 so im a little lost?
Also when logging my autronic wide band it always reads .4 richer than the scantool indicates any way of correcting this?
Cheers shane

[markgammel]

thanks I can use this.

[minytrker]

When I adjust B8021 it doesnt change B8021? What am I missing? When I go back and paste its the exact same.

[GMPX]

Lorenz, you need to reload the file after you save your changes. If that is omitted in the document we should revise it. The file reload is only necessary when changing the zone values (for MAP or RPM).

Cheers,
Ross

[ls1vt209]

Simon and everyone else who has had a hand in this thanks, job well done.

[CV8IIM6]

Thanks for the guide, great work.:good:

In regard to disabling LTFT I found that adjusting B1508, B1509 and B1510 was not enough.

I also had to set B1511 and B1512 (min/max adjustment) to zero.

Cheers.

[joecar]

Including this document for reference purpose...

[pauly24]

Got a couple of questions while following this tute.

It says to set B0141 all to 14.5
With my stock file (VE SS L98 E38) The majority of the points which would be considered in the normal operating zone are all set to 14.63.
Values under ECT of 44 are set to 17.22
and values under intake temp of 0 are extremely rich, starting at 10 and working down to 3.81 for -40.

Would it be stupid to change ALL these values to 14.5?
I mean if the engine is being started for the first time on a super cold morning, then trying to inject 14.5 would cause it to run like crap wouldn't it?

[swingtan]

Page 1, 4th sentence....



Ensure the car is up to normal operating temp before starting this.



Simon.

[pauly24]

Yes but you are changing the point in the map for cold conditions to 14.5.

So next time when you go to start your car tomorrow morning in the cold, it will go to the point for ECT of say 10 degrees and intake vale temp of 10, and it will try and inject 14.5, which is too lean and now your cold start it stuffed.

Are you saying everytime before you drive your car in the morning you must let it cough and splutter because its lean while your waiting for it to warm up? Obviously not but I don't see how it works.

I'm obviously missing something here. :help2:

[gmh308]

Yes but you are changing the point in the map for cold conditions to 14.5.

So next time when you go to start your car tomorrow morning in the cold, it will go to the point for ECT of say 10 degrees and intake vale temp of 10, and it will try and inject 14.5, which is too lean and now your cold start it stuffed.

Are you saying everytime before you drive your car in the morning you must let it cough and splutter because its lean while your waiting for it to warm up? Obviously not but I don't see how it works.

I'm obviously missing something here. :help2:

Its a good point, but maybe the tute covers this re returning to stock values after finishing the tuning session before next cold start. (?).

Certainly if you left the OL run table at 14.5 or ~ 1 EQ/Lambda it would start ok at 10C cold start (the start/cranking is a seperate fueling table) but once started it would probably run a tad rough for a few seconds until the short term trims started up (3 - 10 sec). Or may die and require a restart.

[pauly24]

But why make it so the STFT kick in, it should be set correct so the trims don't have to work, im sure if the mixture is correct first time, and it doesn't need to adjust via triming then this would give smoother operation because it doesn't stumble for a split second with the incorrect mixture.
Maybe the tute should say to only change the values of cells with an ECT over 60 to 14.5
This way you don't affect the cold start of the car.

[gmh308]

But why make it so the STFT kick in, it should be set correct so the trims don't have to work, im sure if the mixture is correct first time, and it doesn't need to adjust via triming then this would give smoother operation because it doesn't stumble for a split second with the incorrect mixture.
Maybe the tute should say to only change the values of cells with an ECT over 60 to 14.5
This way you don't affect the cold start of the car.

STFT's coming in ASAP is to minimise cold start emissions. The OL table wont be as accurate as going into CL type control with STFT's trimming. CL is always going to more accurate as it is based on immediate feedback.

And it will probably stumble for more than a split second if the OL table is set to 1 or 14.5:1 for cold start around 10C. Probably a minimum of 3 seconds if it does not stall. With an IVT/ECT of around 10C its only normally about 20-40% rich anyway (depends on IVT mult value B0146 based on MAP) and will normally run if around 20% lean. Just badly thats all.

So yes probably worth leaving the low temp cells alone, but it depends what your objective is?Are you after full SD MAFless operation?

[swingtan]

The setting of the table to a flat 14.5 is only for doing the VVE. Once you are happy that the VVE is pretty close, you can reset B0141 to what ever works for you. FWIW, it will work fine at a flat 14.63 if you want, as B0146 will help richen up the mixture when cold. Holden ran a very rich cold start, probably in an effort to dump still burning fuel into the exhaust to get the cats up to temp. I've had my car start and idle on a WB reading of 17:1 when it was around 3' one morning. Sounds pretty rough though.......

[pauly24]

I'm not sure what I want to do yet.
I'm just reading through as much stuff as I can to get a better understanding of how it works before I change anything.
But thanks, you have cleared it up now. I guess when we are tuning the car it's never running in these areas anyways.

I have another question about the tute, it says to change parameter B0157 to 70kpa, my stock tune is currently set to 15kpa.
Does this mean after you change it to 70 it will take alot more throttle opening to enable power enrich mode? So even at 60kpa when you could be under a fair bit of load, it will still command 14.5.
Shouldn't the car be running richer under these loads?

[swingtan]

Note also, that the next parameter ( B0161 ) is altered as well. This is just to reset how PE mode is enabled to make it a little more consistent.

There are two main thoughts on how PE mode should be activated...


Throttle Position: This is the default and basically relies solely on the throttle position to enable PE mode. The MAP setting of 15 is extremely low, so the only real control is the throttle position. This mode works pretty well if you really like economy, but it can lead to issues at times, where the car feels slightly sluggish up hills when cruising. This is because the throttle can remain fairly low, but engine load goes up ( and therefore MAP ).
Combined TPS and MAP: I prefer this method as it makes daily driving feel better ( though 'may' increase fuel usage slightly ). In this method, the MAP enabler is set at a point a little above the normal cruise MAP readings ( any where between 70 and 80 kPa ). The TPS on the other hand is set relatively low. Remember that in the E38, the TPS settings in many tables do not directly relate to the logged ETC-TPS PID. There is another thread on this, do a search to read about it. With this setup, the ECM can command additional fueling by entering PE mode on steep inclines, giving the engine a little boost in power. This can help greatly with drivability as you use less throttle, which in turn may prevent a down shift in an auto.


Don't forget the 3rd sentence in the guide....



This document should be read in conjunction with the “Virtual VE Tutorial” provided by EFILive, you should also read through this entire document a couple of times before actually starting any work.


Simon.

[pauly24]

Swingtan, ive got some questions about your methods that I don't agree with (or maybe I don't see the light yet)

First you change all your IAT modifiers to 1, effectively removing any effect IAT has on AFRs.

But then you go log your AFRs and compare them against your IAT and when you see that there off, you fix this by modifying the flow rates of the injectors.
Is this not fudging big time?

Isn't this drift in AFRs caused by the density change of air, eg higher temps, means air is less dense, less dense air has less molecules, less molecules of fuel with same amount of fuel causes it to go lean, which you seen in your IAT vs AFRs.

So shouldnt the IAT table be modified instead of fudging the injector flow modifier?

[swingtan]

Pauly,

You need to stop, sit and think about how tuning with the computer differs from playing with carby jets and distributor weights. You may not agree with everything, but sometimes it's because you may not understand. here's a very basic rundown of the basic tuning principles when dealing with a computer managed system.


Understand the current system and how it works: The computer managed system is much, much more complicated than distributors and carbies. When dealing with physical devices, it's easier to see how they work and what effects changes will make. It doesn't work the same with the computer.
Understand what the settings in the tune file do and how they effect each other and the final engine management: Many tables are cross referenced with other tables. Settings turn off / on entire sections as well as alter settings under different conditions.
Start tuning by "base lining" the engine: Because of the complexity of the management system, you MUST get the basics right. Sure you can go out one day and fudge the fueling tables to look right for that day, but if conditions change, the fueling will probably go right out.
Make small and calculated adjustments: Pretty self explanatory really.
Make one or two adjustments at a time: Again, std tuning rules. Change too much and you have no idea what helped, if anything. Maybe one change helped and one made things worse and they canceled each other out.
Never assume that what you think is correct, especially when starting out: You will see people on here that have been tuning for many years asking basic questions again, just to be sure. There is no shame in this, we all forget things. It'd be much more embarrassing to get something wrong and damage a motor.


Now, getting back to your slightly sparse questions....


When you talk about IAT modifiers, I'm assuming you mean {B0146}. You didn't specify so I'm guessing.... This table is used to add commanded fuel depending on the IAT. In certain circumstances, you want to alter the commanded fuel, especially at cold starts. So you can richen up the commanded fuel with this table. You don;t really want to be commanding lots of different AFR's when setting up the VVE as it just makes thing more confusing, so you set it all to 1 to ensure it doesn't move things around on you.
Is it fudging? No, you couldn't be more wrong in this case. When adjusting the Injector Flow Rate vs IAT, you are correcting the supplied fuel amounts for what the engine needs. You are measuring the exhaust AFR's with the WB and adjusting the flow rates to ensure that the actual AFR matches the commanded AFR. If you used {B0146} to correct this drift, THEN you would be fudging the tune as you have not matched the commanded vs exhaust AFR's just altered the commanded to get the value you wanted.
Yes, as the IAT increases, the air is less dense so less fuel is needed.
No, the IAT table should be used to "command" a different AFR depending on the IAT. It should not be used to "correct" the mixture because other parameters are out of calibration.


Simon.

[pauly24]

Arh simon, sorry I understand now. Your answer and an answer to another post of mine cleared this up for me.

I thought the IAT scalar was a scalar that is used to calculate the mass of air, ie when its hotter the air is less dense and hence less mass of air for same given volume. But this is not the case, as you mentioned the IAT scalar is just used to command different AFRs (like for a choke on cold mornings)

What I was thinking the ECM does automatically when it looks at the VE table, having values of g.K/kPa, it multiplies this by temp and divides by pressure to give mass of fuel. I thought by scalaing the IAT table to 1, you are removing this step the ECU does to work out the mass of air, but I was wrong.

Things are much clearer now, thanks.

[pauly24]

Why do you have to disable the fuel trims when you force the car to stay in OL mode? If your in OL mode I thought the trims don't work anyways.

[swingtan]

They are the same thing, do one and you do the other.....

IE. Disable STFT = OL mode

[swingtan]

Arh simon, sorry I understand now. Your answer and an answer to another post of mine cleared this up for me.


Lol.. I read that whole post with a Pirate voice :p

[pauly24]

hahaha, laughing at my stupidity aswell, I've read over your tute so many times. Don't know how I thought they were different, its clearly obvious. Thanks.

[joecar]

Links for easy reference:
E38 VVE Setup Guide (http://forum.efilive.com/attachment.php?attachmentid=4354&d=1229048532)
Virtual VE Tutorial (http://forum.efilive.com/attachment.php?attachmentid=8002&d=1274505151)

[Dieselman]

Hello everybody,

Well I finally got around to setting up my wideband and did a bit of logging but I think I stuffed up on the PID selection.

I selected GM.AFR instead of E38.AFRATIO :bad:

Is there anyway I can save this log or is it toast???

If anyone can see what else I am missing a few pointers would be appreciated. I am using a Tech Edge 2J2 wideband with a serial connection and tuning a L98 VE Commodore


Thanks in advance

[swingtan]

Well....

You only have 22 min worth of log data there, so you are going to be cutting it close to the minimum amount of data needed. I prefer to run logs of over 30 min, preferable over 60min when using street based logging. On the dyno you can use a much shorter log as you can hit the required cells more often. However, you can still use this log even though you didn't log E38.AFRATIO.

What I'd do is check the tune settings for PE mode, and then filter out PE mode in scantool. You can then assume that the commanded AFR will always be stoichiometric ( or what ever was commanded, but it'll be fixed ). So you can make a custom PID to display a fixed BEN Factor for the commanded AFR vs the WB reading.

Then invert the filter and do the same for PE mode, as if you set up PE as in the tutorial, then it should be a fixed setting as well. If you get really tricky, you can make a custom PID to work with both cruise and PE mode in one hit.

It's a bit of work though and would be a little tricky, but it could be done. Or just redo the log using the correct PID's. I was talking someone else today about this and mt suggestion was to log the drive to / from work for a couple of days and then use the log joining tool to combine them into a single log. Then after filtering the data, use the combined logs to apply the changes to the VVE. When getting log data, keep changing gear up and down to vary the RPM and load, this gives lots of good data.

Simon.

[Dieselman]

Thanks for the reply Simon

I only did a small run today just to make sure everything was working ok. I will do some more logging once I know everything is set up correctly!!

I will just put today down to experience - or lack of it :grin:


Ben

[wesam]

I don't know if I'm wrong but i thing the B0169 and B0170 which are factors should be increased not decreased to ramp the fuel faster
the stock tune came with a value of 1
in tutorial the value is 0.1
i think we should use some thing like 1.2 for N/A cars and 1.5 for FI cars

[swingtan]

The tutorial deals specifically with...


The tuning of the VVE, which does not really care about how fast PE mode is ramped in. In fact, the slower that things happen during tuning the VVE, the better the result would be.
The OS that I was working on at the time. In this case, the OS had values of something like 0.01 for PE fuel ramp in/out (from memory). Depending on how you were controlling PE, you could have any value for these tables. It all comes down to giving the motor what it wants.


I've seen values of 1 and higher used, personally I don't go that high but that doesn't mean other values are wrong.


Simon.

[PRAY]

Will this only work in OLSD? I remember in the LS1 days I would keep the STFT's turned on and let the car go into CL if I didn't have a WBO2 in the car and just use those to tune the Driving portion. It seemed to work well then. I would use the dyno for the WOT stuff then convert back to the MAF and match it up accordingly. I want to start tuning customers cars with the VVE first like I used to but have been affraid of the tables and have been getting good results with just adjusting the MAF and PE. I hate tuning that way and it goes against what I believe in. Also, when I re-enable the MAF, is that done in OLSD off the WB or could I use the STFT's to tune that also? At the end of all this, is it bad to re-enable the LTFT's? Seems that it may help fine tune everything over time as the engine and conditions change. Thanks.

[swingtan]

In short, yes you can use the STFT's as long as you ensure the LTFT's are either off and cleared, or you add in those corrections as well. It may also badly mess up your OL / PE fueling so you need to be really careful there.

As for MAF vs MAF-less, I've done both for extended periods of time on my car. Personally I prefer running the MAF as the fueling is much more accurate and I can easily run OL with minimal drift between the WB AFR and the commanded settings. In the end though, there is no real difference to an every day driver between MAF or MAF-less.

Simon.

[GabrielMga]

Man...this looks a bit difficult and hard-working for me, that I´ve never worked before.

[PRAY]

It's not that difficult. I just re-read throught the tutorial yesterday and set up my tune accordingly. I won't have a chance to implament it till June but the "hard" part is done. Just have the tutorial open in one screen and your tune open in the other side by side and go down the check list. Very easy that way. I really liked that you addressed the IAT vs. AFR issue. Could that also be taken care of in the IAT scaler? I am going to use the IFR scaler as suggested but I was just wondering if the IAT scaler would work like in the old days.

Afte re-reading the tut. again I am going to leave the LTFT's off like I used to and only use STFT's again. The WOT addition or subtraction of them bothers me. I am also seeing the benefits of having the MAF in place for many reasons. Just never liked the thing in the past but it seems that the factory has come a long way on these and they are no longer a restriction or hinderance. When going back to the MAF after all your OL adjustments are done do you return all the tables to stock except the LTFT's? I.e. The OL commanded fuel tables and what not? Also, when you are turning off P0101-3 is it just the lamp or do you turn them off in both diagnostic tables? Seems if you hit them in both tables the car can't recognize if the MAF is still there like deleating the rear 02's. Therefore you won't have to remove the yellow wire from the connector. I just don't know if you do that if you are messing with some of the other check tables that need to be seen by the computer. Great wright up. Thanks.

[joecar]

Man...this looks a bit difficult and hard-working for me, that I´ve never worked before.What vehicle and engine do you have...?

[GabrielMga]

What vehicle and engine do you have...?

In fact, I m going to buy one FlashScan, so after reading this setup tutorial, this tuning process looks a little difficult because I didn´t make any vehicle.
But maybe this can be more hard-working initially...;)

[joecar]

Bump.


Links for easy reference:
E38 VVE Setup Guide (http://forum.efilive.com/attachment.php?attachmentid=4354&d=1229048532)
Virtual VE Tutorial (http://forum.efilive.com/attachment.php?attachmentid=8002&d=1274505151)

[TurboCamaro]

Yes, I got that. I did some testing last weekend and setting "DTC Type" to "X: Not reported" is not very helpful. there are 2 possible results from doing this.


If the MAF is still plugged in correctly and functioning, it will still be used for air flow measurements as you have just told the ECM to ignore any MAF failures. So it will continue to use the signal coming from the MAF, even if the test settings say it should have failed.

If the MAF has been disconnected, the car will start and then stall as it will get no fuel. As the PCM has been told to ignore MAF failures and the MAF is disconnected, it will read the air flow as the minimum MAF setting ( in my case 0.55 gm/S ). Given the very small airflow being used, the PCM will simply not inject any fuel and the engine will stall.



So the idea would be to set the following:



If you are planing on going back to using the MAF, the changes should be...


DTC MIL - P0101 = No MIL
DTC MIL - P0102 = No MIL
DTC MIL - P0103 = No MIL

and optionally

DTC Type - P0101 = C: Non Emissions
DTC Type - P0102 = C: Non Emissions
DTC Type - P0103 = C: Non Emissions

All these will need to be returned to stock when the MAF is returned to service.

If you are going to remain MAF-less...



DTC Type - P0101 = C: Non Emissions
DTC Type - P0102 = C: Non Emissions
DTC Type - P0103 = C: Non Emissions

DTC MIL - P0101 = No MIL
DTC MIL - P0102 = No MIL
DTC MIL - P0103 = No MIL




Is this the case for the E67 as well? Will it be consistent that the engine won't start? Or could it start and run fine at times?

[MyM8V8]

Guys. Will the Efilive VVE tutorial and Swingtans VVE set up still be ok for a 2015 Gen F Maloo (R8 SV pack 340kW. T43 6L80E).

Thinking of smallish cam, intake and CAI with 1 7/8" LT headers and 3" duals.

Thanks.

[joecar]

Bump again.


Links for easy reference:
E38 VVE Setup Guide (http://forum.efilive.com/attachment.php?attachmentid=4354&d=1229048532)
Virtual VE Tutorial (http://forum.efilive.com/attachment.php?attachmentid=8002&d=1274505151)

[jmsmotorsport]

Couple of questions on this tutorial, It says to alter the VVE above normal RPM range and also in the low MAP area - What is a suitable value here?
Once finished with the VVE correction which tables are returned back to factory when staying SD (MAFless). It also mentions resetting AFR's - Is this back to factory in the B0141, B0143, B0146, B3618? Im sure i will have more as I get my head around the VVE system rather then the old LS AutoVE way.

[joecar]

If you want to run MAF-less, you leave the MAF failed (with MAF DTC showing up).

If you want to run CL you have to restore the settings for the CL/LTFT/STFT tables that you disabled to do VVE.

After flashing, you use the scantool to reset trims.

[jmsmotorsport]

So it is very much the same as the Auto VE except the smoothing part. So I leave the AFR tables so it's either commanding 14.5 cruise or 12.5 WOT? Or do I return these to the factory settings aswell?

[joecar]

Yes, it's very much the same as AutoVE.

Yes, leave the cruise/PE tables set at 14.5/12.5 (and verify that you see these values at the wideband, if you do then it means the VE/VVE is close).

[jmsmotorsport]

Yep have been doing that and it's getting close some mid throttle points around the 3-4K rpm range it's up around the 15.3 AFR so needs some work in this range. I have my E38 BEN Map set up showing 3 decimal points and used the copy and fill process to hit some areas I didn't get up to the 50 count. I also went from 6400 rpm and I copied and pasted into the next rpm range and took 1% and continued this right up to 8000rpm to flatten off the end of the VVE table. I will go for another log tonight hopefully temp drops as its 37 hear today.

[jmsmotorsport]

Also once in OL does the engine run only in the low octane spark table like the ls1?

[jmsmotorsport]

If you want to run MAF-less, you leave the MAF failed (with MAF DTC showing up).

If you want to run CL you have to restore the settings for the CL/LTFT/STFT tables that you disabled to do VVE.

After flashing, you use the scantool to reset trims.

You say mafless you just leave the maf failed? I'm still able to be mafless and run my LTFT and STFT is this correct? So would this make it a CL SD Tune? And by being in CL with STFT active will account for IAT temp changes? Sorry if this seems dumb.

[joecar]

Also once in OL does the engine run only in the low octane spark table like the ls1?No, it runs from both (adaptive knock retard).


EDIT: BUT in SD it runs from the LO spark table only, regardless of CL/OL.

[joecar]

You say mafless you just leave the maf failed? I'm still able to be mafless and run my LTFT and STFT is this correct?
Yes, correct.


So would this make it a CL SD Tune?
Yes, correct, CLSD or SDCL.


And by being in CL with STFT active will account for IAT temp changes? Sorry if this seems dumb.
VE is a combination of cylinder actual-fill airmass normalized for temperature and pressure (using the Ideal Gas Law from Physics class)...

and the VE table is looked up and/or calculated using MAP as one of the parameters...

so, if injector tables are correct, and other things line up, then SD tune will work when pressure and temperature change...

now, in the real world, sometimes it does not work for various reasons... but there are many instances of various people's SD tunes working fine, even with altitude change.

[jmsmotorsport]

No, it runs from both (adaptive knock retard).

Ok so when tuning timing I only need to alter the high octane table and leave the low octane only as a safe guard.

[jmsmotorsport]

Yes, correct.


Yes, correct, CLSD or SDCL.


VE is a combination of cylinder actual-fill airmass normalized for temperature and pressure (using the Ideal Gas Law from Physics class)...

and the VE table is looked up and/or calculated using MAP as one of the parameters...



so, if injector tables are correct, and other things line up, then SD tune will work when pressure and temperature change...

now, in the real world, sometimes it does not work for various reasons... but there are many instances of various people's SD tunes working fine, even with altitude change.

I have found that the IAT temp doesn't cause to much AFR drift until around the 53 degree up range so I am going to sort this out first before going any further with my VVE tuning. Initially when checking this at the start I could only get the IAT to 50 through heat soak and didn't think it was an issue but after a hotter day and higher IATs it's become an issue.

[jmsmotorsport]

Ok have started doing the IAT correction, it swung out to 15.40/15.50 and commanded is 14.55 @ 60 degrees c so I applied the correction and am fine tuning but I noticed while watching the w02 that when I turned the AC on or off it changed my AFR buy around .5 so the question is do I correct the IAT with AC on or off?

[joecar]

Ok so when tuning timing I only need to alter the high octane table and leave the low octane only as a safe guard.
I should have been more precise:
OL: runs adaptive spark (i.e. both HO/LO tables).
SD: runs LO table only (for LS1B you would need a COS to run HO/LO).


If you're running MAF then yes edit the HO table only.
If you're running VE/SD then copy HO to LO and edit LO.

If you're running a COS (LS1B), then VE/SD uses HO/LO.

I don't know how this is handled in E38/E67 (there's no COS).

[jmsmotorsport]

Cheers for clearing that up joe.

Now my IAT tuning, commanded is a fair bit off actual AFR while idling away heat soaking but since modifying the Injector factor the AFR doesn't creep as IAT temp rises, I understand that is now fixed, correct? And now I have to dial my VE in to get it back to commanded?

[jmsmotorsport]

Original - Don't mined the huge jump at the start, turned AC on. But you can see as IAT was rising the AFR marginally drifted.

Updated - After ECT came to temp and Commanded AFR settled at 14.55 the AFR never drifted from 13.30 as the IAT rose.

I will need to check this all again once temps cool down, start up IAT is already at 34. But at this stage I am satisfied that IAT temp wont affect me BEN MAP while logging out on the road to dial my VVE in.

[joecar]

I should have been EVEN more precise:

- runs HO/LO adaptive spark when there are no MAF DTC's, regardless of CL/OL.
- runs LO table only when MAF DTC's are present (and possibly other DTC's), regardless of CL/OL.

so then:
OLMAF and/or CLMAF: runs adaptive spark (i.e. both HO/LO tables).
OLSD and/or CLSD: runs LO table only.

for LS1B, in SD, to run HO/LO adaptive spark, you would need a COS.

[joecar]

Also, does the pid SAE.LAMBDA work...?

[joecar]

Original - Don't mined the huge jump at the start, turned AC on. But you can see as IAT was rising the AFR marginally drifted.

Updated - After ECT came to temp and Commanded AFR settled at 14.55 the AFR never drifted from 13.30 as the IAT rose.

I will need to check this all again once temps cool down, start up IAT is already at 34. But at this stage I am satisfied that IAT temp wont affect me BEN MAP while logging out on the road to dial my VVE in.Ok, good.

Can you account for the difference in AFR from 14.55 to 13.30...?

[jmsmotorsport]

Ok, good.

Can you account for the difference in AFR from 14.55 to 13.30...?

I wil start to fiddle with the VVE around the idle area and see if that improves it if not I will start to look elsewhere. I'm fairly certain I should get it in the VE as when revs change from AC on to AC off the AFR moves around so my thinking was there is some differences in VE at this MAP and RPM points

[jmsmotorsport]

I wil start to fiddle with the VVE around the idle area and see if that improves it if not I will start to look elsewhere. I'm fairly certain I should get it in the VE as when revs change from AC on to AC off the AFR moves around so my thinking was there is some differences in VE at this MAP and RPM points

adjusted the VVE based on the BEN MAP for the IDLE area and nothing changed with W02 AFR so not sure if I'm adjusting the VVE right or the W02 is displaying a false reading. Once I multiply with the figures from my BEN map I generate coefs and then generate VVE is this correct?

[jmsmotorsport]

Also, does the pid SAE.LAMBDA work...?

Yes I have now selected it for further logging.

[joecar]

adjusted the VVE based on the BEN MAP for the IDLE area and nothing changed with W02 AFR so not sure if I'm adjusting the VVE right or the W02 is displaying a false reading.At idle, if cam has sufficient overlap, you may get unburnt fuel/oxygen passing into exhaust, this registers lean on wideband, and when you correct for this in VE/VVE it seems to make no difference.


Once I multiply with the figures from my BEN map I generate coefs and then generate VVE is this correct?Yes. correct.

[jmsmotorsport]

At idle, if cam has sufficient overlap, you may get unburnt fuel/oxygen passing into exhaust, this registers lean on wideband, and when you correct for this in VE/VVE it seems to make no difference.

Yes. correct.

Standard cam so overlap won't be an issue, I'm showing rich at idle so I guess I just need to keep dialling in the VVE in this area until it's the same as commanded.

I also have a odd start issue where it starts and then split second it stumbles the just idles perfect.

[jmsmotorsport]

Also what is the difference between the VVE OPEN and the VVE CLOSED?

[joecar]

IMTV = intake manifold tuning valve (i.e. intake manifold variable length runners)

open and closed are the two positions (open = long runner, closed = short runner, unless I got them vice-versa)


if engine is not fitted with IMTV then use the IMTV Open VVE tables.

[joecar]

Standard cam so overlap won't be an issue, I'm showing rich at idle so I guess I just need to keep dialling in the VVE in this area until it's the same as commanded.

I also have a odd start issue where it starts and then split second it stumbles the just idles perfect.Try it, but note that the VVE surface should "flow" and not have any abnormal/sudden change.

[jmsmotorsport]

IMTV = intake manifold tuning valve (i.e. intake manifold variable length runners)

open and closed are the two positions (open = long runner, closed = short runner, unless I got them vice-versa)


if engine is not fitted with IMTV then use the IMTV Open VVE tables.

Ah yep that makes sense. Thanks for clearing that up.

[jmsmotorsport]

Try it, but note that the VVE surface should "flow" and not have any abnormal/sudden change.

Yep there isn't any crazy steps in it, if it's not my VVE then where should I be looking to get my idle AFR back closer to the commanded? Or is it a case of leaving it since it idles happily at these numbers.

[jmsmotorsport]

I'm not sure what I'm doing wrong but I cant seem to get this VVE process working. it either causes huge peaks in areas and huge dips in others unless I use the copy and fill process, but when I use that it seems to change my logged data to much and don't get the desired effect in AFR? I have tried to attached a log but it wont so here is the latest tune file after applying this BEN Map.

19253

19254

[jmsmotorsport]

Found my problem, if you set map precision to 3 any numbers over 1 become .025 ect if it's set to 2 the number shows 1.02. So every time I would paste and multiply it would cause issues. In the mean time any rich spots have been sorted but all the lean spots never changed as they would multiply by .025 cause a huge hole then get smoothed out once I would gem coefficient and vve

[Mrbowtie26]

Would this tutorial apply to a 2015 Camaro SS with E38 ?
Thanks

[ScarabEpic22]

Would this tutorial apply to a 2015 Camaro SS with E38 ?
Thanks

Yes, all E38/E67 and the general concepts apply to the E78/E39/E39A/E92 with some minor tweaks.

[joecar]

E92 requires a calc pid for MAP:BARO ratio (which is used to reference the axis of the VVE tables)...

i.e. define CALC.MAP_BARO to be {SAE.MAP.kPa}/{SAE.BARO.kPa}.

[joecar]

Bump again.


Links for easy reference:
E38 VVE Setup Guide (http://forum.efilive.com/attachment.php?attachmentid=4354&d=1229048532)
Virtual VE Tutorial (http://forum.efilive.com/attachment.php?attachmentid=8002&d=1274505151)

[joecar]

Make the MAF fail (i.e. force a MAF DTC immediately (you might have to increase the very low end of the MAF so engine can start and then throws a MAF DTC))... and go from there.

[joecar]

You mean link the scantool to the tunetool... there is a setting for this.

[joecar]

Oh, yes, there's a log joining tool somewhere, I don't remember where it is... if you have multiple logs, the joining tool joins them together... just try it, you'll see how it works.

[GhostXR]

Question about the commanded AFR's - I had to scale the injectors in my 2008 Avalanche e38 by roughly 20% (did it by multiplying IFR table by 0.8 and dividing the stoich table by 0.8). Now that the afr table is different does this affect the desired fuel ratios referenced in the tutorial? Ie. If my stoich ratio for gasoline is now referenced as 16 instead of 14.7 (don't have exact numbers in front of me, sorry) due to the scaling do I also need to account for that 20% difference when entering the commanded/desired afr?

[joecar]

Use EQR units to view the AFR table (i.e. the PE table).

[GhostXR]

Thanks, that's what I kind of figured. BTW, I scaled B4001 "Injector Flow Base" by multiplying it by 0.799 and scaled B3671 "Stoichiometric AFR" by dividing by 0.799 - I hope that's the correct way to scale?
What was throwing me off is when I was looking at commanded AFR PID it showed that it was commanding 15-16 AFR even under PE. I'll have to read up how to change the BEN calculations to use Lambda or EQR instead of AFR since my wideband shows normal AFR ranges which is throwing the whole correction factor out of whack because the wideband serial readout is not scaled...

[joecar]

Yes, correct...

( stated generally: multiply or divide IFR or stoichAFR by inverse scale factors )

i.e as you have it, set B4001 to (IFR * X) and set B3672 to (stoichAFR / X) where X is 0.799.

Yes, please use EQR.

( I use EQR for commanded fuel, and Lambda for exhaust measurement... this allows me to avoid confusion when speaking )

Post your calc_pids.txt here.