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ECMlink New SD setup Hoping to have some "wiseman" check my logs

Tony J

Proven Member
32
6
Oct 2, 2020
Belleville, ON_Canada
Just recently converted to speed density, I have the car dialed in pretty good cruising and what not but at WOT it seems to get knock 2/4 pulls

FIC 1250cc injectors
255 walbro
-6 lines everywhere
fuel lab filter
aeromotive fpr set to 40 psi
fp red turbo
greddy bov
2.5 inch piping
mishimoto intercooler
3 inch exhaust
external wastegate tial 38mm

balance shaft delete
fresh timing job less than 100 km ago
fresh plugs br8es i believe, gapped to .20 if im not mistaken.

car idles great.

Any suggestions would be muchly appreciated!
 

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  • Couple bigger pulls unmodified map.ecm
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Stapl3

15+ Year Contributor
1,597
167
Oct 27, 2004
MI, Michigan
You will pull your hair out trying to get it physically at .63. It is so damn sensitive.

To clarify, you’re saying that you trust the wideband and the ecm AND injector size more than the fuel pressure gauge?
Lets put it like this. I only care about afratioest = actual wideband. My cars don't have one gauge on them. If I have 1000cc injectors, I'll put that into link for the global % then I'll turn the afpr blindly until afratioest and the wideband line up. Now there's other aspects like deadtime, but that's the big majority of it. It doesn't even matter if the injectors really are flowing 1000cc and the gauge really is at exactly 42.5psi. All we're trying to do here is make the ECU happy, nothing else. ECU thinks it's putting out a target a/f ratio, make it so.

To go slightly further, the sign of a perfectly setup car is, at peak VE, Afratioest=wideband AND boostest=boost AND the airflow adjustment either be 0 on the slider or 100 on the SD table. Again, those are all to occur at peak VE. If those 3 things don't occur at peak VE, then your numbers in ecmlink will always be skewed and you'll be adjusting the airflow to compensate for an incorrectly calibrated fuel system. You'll target a desired ratio on the DA table and won't get what you want. The mess compounds quickly. But when it's set up correctly, it's an absolute joy to drive and tune. Difference is night and day.
 
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Tony J

Proven Member
32
6
Oct 2, 2020
Belleville, ON_Canada
You will pull your hair out trying to get it physically at .63. It is so damn sensitive.


Lets put it like this. I only care about afratioest = actual wideband. My cars don't have one gauge on them. If I have 1000cc injectors, I'll put that into link for the global % then I'll turn the afpr blindly until afratioest and the wideband line up. Now there's other aspects like deadtime, but that's the big majority of it. It doesn't even matter if the injectors really are flowing 1000cc and the gauge really is at exactly 42.5psi. All we're trying to do here is make the ECU happy, nothing else. ECU thinks it's putting out a target a/f ratio, make it so.

To go slightly further, the sign of a perfectly setup car is, at peak VE, Afratioest=wideband AND boostest=boost AND the airflow adjustment either be 0 on the slider or 100 on the SD table. Again, those are all to occur at peak VE. If those 3 things don't occur and peak VE, then your numbers in ecmlink will always be skewed and you'll be adjusting the airflow to compensate for an incorrectly calibrated fuel system. You'll target a desired ratio on the DA table and won't get what you want. The mess compounds quickly. But when it's set up correctly, it's an absolute joy to drive and tune. Difference is night and day.
Ahaha yep I have lost my mind setting it but having now 3 dsms I think it's funny how many guys over look the simple idle steps.

I learned quick to get support in this forum or even forums alike you better atleast know what you're trying to do or looking for. Everything sounded so foreign but these forums really are amazing when you know what to look for.

I appreciate all the advice guys. I'll go for some drives tomorrow out of boost and see how we make out and post a log
 

Tony J

Proven Member
32
6
Oct 2, 2020
Belleville, ON_Canada
Lower the Knock Sensor Control so that the ecu can try to save the motor for when you eventually move back to power pulls. The below are acceptable settings.

Activate when engine RPM = 3000
Activate when TPS = 50%
Noted, Will do.
 

Stapl3

15+ Year Contributor
1,597
167
Oct 27, 2004
MI, Michigan
Going through the log, you're still lean a little. I averaged the values in the log and it's about half point off. So I would give the afpr 1/4th of a turn clockwise. Great work though, looks so much better.

If possible can you lock the ECU in openloop for the cruise and idle? That would really tell the story without the ECU doing adjustments. Instead of the erratic up and down adjustments, you'll just see a nearly straight line. A lot easier to look at that and make the adjustments at this point. You'll be impressed how you can get them within a percent of each other if you really go at it. They will nearly cover themselves through the log which is satisfying AF.

As for timing, instead of loading in the 2g tables you could just copy your Minoct table over to your Maxoct table so both are the same. Ultimately we just want timing pulled so we can put it back properly and inch it back up to a safe level. No stock table you load will be ideal necessarily, because they're designed around a turbo that has full boost under 3k and you're now using a fp red. That table will need some work but I'm down to have at it for you. A WOT pull from lower than ideal RPM to minimum peak VE (~6700) is required though.

I learned quick to get support in this forum or even forums alike you better atleast know what you're trying to do or looking for. Everything sounded so foreign but these forums really are amazing when you know what to look for.
You're in the right spot now, just stay in this groove and we'll get you there. And for ffs stay away from facebook nation or whatever that is LOL That's like asking a eBay seller how to tune your car, yikes.
 

llxkevinxll

10+ Year Contributor
489
231
Jan 29, 2012
Milwaukee, Wisconsin
Going through the log, you're still lean a little. I averaged the values in the log and it's about half point off. So I would give the afpr 1/4th of a turn clockwise. Great work though, looks so much better.

Can you explain why you recommend using the fuel pressure regulator as a tuning tool instead of the VE table, global fuel, etc.? I'm no tuning wizard but I've done my fair share of reading and research over the years and I've never seen this suggested.
 

Stapl3

15+ Year Contributor
1,597
167
Oct 27, 2004
MI, Michigan
Global fuel % and base fuel pressure are dance partners. They are one in the same. I like to adjust the AFPR because it's simple and a mechanical adjustment. You could do global % instead but I don't know what affects that will have elsewhere in the ECU. Most likely none? Not sure.
The gauge doesn't have to read 42.5. The number in 'link doesn't have to be the number scribed on the injectors. One of my cars I run 650s at 80psi base and it's absolutely amazing.

The VE table is airflow. If you up the VE [ahem SD] table in some spots by 20%, well you got a basic fueling issue, the other times you're not adjusting 20%, the ECU is adding because it's in closed loop and all is good, right? No. Look at the first log of this thread and you'll see exactly this. Using airflow adjustments as fuel adjustments is flat wrong. And anyone that says scale the entire VE table by, say, 5% doesn't know what they're doing. If you have to adjust ALL your airflow to get 5% change, well your fuel calibration is off instead.

When the fuel system is calibrated correctly, you'll be surprised how little you'll touch the SD table / sliders. Little to none. Getting the fuel system properly calibrated on a dsm with 'link is straight up 90% of the game.
 
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llxkevinxll

10+ Year Contributor
489
231
Jan 29, 2012
Milwaukee, Wisconsin
Global fuel % and base fuel pressure are dance partners. They are one in the same. I like to adjust the AFPR because it's simple and a mechanical adjustment. You could do global % instead but I don't know what affects that will have elsewhere in the ECU. Most likely none? Not sure.
The gauge doesn't have to read 42.5. The number in 'link doesn't have to be the number scribed on the injectors. One of my cars I run 650s at 80psi base and it's absolutely amazing.

The VE table is airflow. If you up the VE [ahem SD] table in some spots by 20%, well you got a basic fueling issue, the other times you're not adjusting 20%, the ECU is because it's in closed loop and all is good, right? No. Look at the first log of this thread and you'll see exactly this. Using airflow adjustments as fuel adjustments is flat wrong. And anyone that says scale the entire VE table by, say, 5% doesn't know what they're doing. If you have to adjust ALL your airflow to get 5% change, well your fuel calibration is off instead.

When the fuel system is calibrated correctly, you'll be surprised how little you'll touch the SD table / sliders. Little to none. Getting the fuel system properly calibrated on a dsm with 'link is straight up 90% of the game.
When running large injectors, especially low-Z, we would eventually get poor idle quality due to high base fuel pressure pushing the injection duty cycle/injection time way too low. So there is a limit to our ability to use base fuel pressure in this manner. And "airflow adjustments" are fuel adjustments in this sense. The ecu only has control over the fuel through the injectors. It has no control over airflow (arguments could be made against that statement for vehicles with DBW, variable cam timing, closed loop boost control etc). You aren't demanding airflow with the VE map. You are telling the ecu what reality is so it can deliver fuel appropriately. Ecmlink has no provision for me to ask for specific fuel injection time values. I only have essentially one table. And it's the SD table (and min/maxoct AFR Demand tables I guess). The global fuel setting and other basic fuel parameters are really scalars for the entire VE map. As you mention, when your global is out of sync with injector size and base fuel pressure your VE map gets wonky.
 

Stapl3

15+ Year Contributor
1,597
167
Oct 27, 2004
MI, Michigan
Very interesting on the low-z information, thanks. Kinda makes me think they were sub-par. All these years...

The ECU has control over fuel ratio from the OpenLoopMaxOct table in DA. That's the entire crux of the whole thing and me over saying to calibrate shit as perfectly as possible. When you type 12.8 in a cell on that table, you want 12.8 when the cell is used. Anything other than that is like looking at a digital alarm clock and saying it's one hour 18 minutes off, it's [really] this time. Why?

Otherwise I do agree 1000% with you and the 2am is catching up as I read and reply now.
 

jed344

Supporting VIP
1,182
285
Jan 10, 2008
Waterville, Iowa
Looks like a 1g timing table? That will end up to aggressive for what you are trying to do. For the injector sizing with SD i like to set the speed density table to 100% ve 5-5500rpm is likely where yours would hit that. Then adjust global fuel so it lines up target AF and wide band at that point. I also would change your DA fuel table to the target air fuel you want. Then i go back to idle. Use the idle cells in SD table to get the airflowperrev to the value you want. Depending on cams and other factor .25-.35. The higher end of those values i usally only end up on with a car with something like the S3's and idle rpm of 1krpm+. Then use dead time or Inj bat adjust table to get the short term fuel trims to within 5%. From my own experience this has yielded the lb/min calculation to be very close to what the car makes on the dyno. Made me feel it was the correct way to do it as the ecu's idea of air flow was correct so the fuel side of things should be too.
 

danl

20+ Year Contributor
721
117
Apr 8, 2002
Severn, Maryland
To go slightly further, the sign of a perfectly setup car is, at peak VE, Afratioest=wideband AND boostest=boost AND the airflow adjustment either be 0 on the slider or 100 on the SD table. Again, those are all to occur at peak VE. If those 3 things don't occur at peak VE, then your numbers in ecmlink will always be skewed and you'll be adjusting the airflow to compensate for an incorrectly calibrated fuel system. You'll target a desired ratio on the DA table and won't get what you want. The mess compounds quickly. But when it's set up correctly, it's an absolute joy to drive and tune. Difference is night and day.

I'm likely beating a dead horse here or perhaps I don't understand what is written (often the case for me). It is my understanding that even outside peak VE, this is true. The SD table is used to compensate for different volumetric efficiencies seen at different points in the RPM and pressure table. The ECU then takes this information when making AFR and BOOST estimations.

Now, there are multiple reasons why we may not see this in practice (non linear injectors, incorrect injector dead time values, MAP sensor placement, MAP sensor accuracy/linearity, etc....). However in theory, that is how I believe it to work.
 

Tony J

Proven Member
32
6
Oct 2, 2020
Belleville, ON_Canada
Logs from today, had a buddy driving while i watched logs... was getting a small amount of knock .4 at wot Im thinking this is just phantom knock? log attached
 

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  • PULLS WITH MATT.elg
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Stapl3

15+ Year Contributor
1,597
167
Oct 27, 2004
MI, Michigan
I'm likely beating a dead horse here or perhaps I don't understand what is written (often the case for me). It is my understanding that even outside peak VE, this is true. The SD table is used to compensate for different volumetric efficiencies seen at different points in the RPM and pressure table. The ECU then takes this information when making AFR and BOOST estimations.

Now, there are multiple reasons why we may not see this in practice (non linear injectors, incorrect injector dead time values, MAP sensor placement, MAP sensor accuracy/linearity, etc....). However in theory, that is how I believe it to work.
BoostEST is only accurate at peak VE and should be pretty much ignored at all other times. Afratioest I make line up during idle, cruise, and throughout the pull. Pretty much all the time.

The whole thing with Boostest = boost AND afratioest = wb AND the airflow slider be at 0 or SD table cell being at 100, all 3 of those things occurring at peak VE means the fuel system is perfectly calibrated. Then there is nothing to touch with the afpr or global. Any adjustments (spare messing with deadtime) before and after peak VE would be completely done with the mafcomp sliders or the SD table.


As for the log above, look at the relationship between afratioest and wideband throughout the pulls. The ECU is targeting 9.4 but the wideband is reading in the 10's. Again, you're lean dude. Turn the afpr clockwise and then do a pull, and keep adjusting the afpr until afratioest = wb. Any adjustments with the SD table will be a complete waste of time until the fuel system is calibrated correctly.
 
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llxkevinxll

10+ Year Contributor
489
231
Jan 29, 2012
Milwaukee, Wisconsin
Turn the afpr clockwise and then do a pull, and keep adjusting the afpr until afratioest = wb.

As for the log above, look at the relationship between afratioest and wideband throughout the pulls. The ECU is targeting 9.4 but the wideband is reading in the 10's. Again, you're lean dude. Turn the afpr clockwise and then do a pull, and keep adjusting the afpr until afratioest = wb. Any adjustments with the SD table will be a complete waste of time until the fuel system is calibrated correctly.

I, as we discussed above, disagree with the adjusting the FPR approach here:

1. WB Factor is not consistent during the pull, it swings from 10% to nearly 20%. That means a global change will not correct all of the fueling disparities.

2. Adjusting global fuel % will result in an identical response as you are suggesting with the regulator change. It will move all fuel everywhere. And the cruise section right at the beginning doesn't need nearly as much adjustment as during WOT. Why mess up cruise to not fix WOT?

3. As we increase base fuel pressure, and thus the rising rate fuel pressure peak, we are moving the fuel pump farther and farther up its pressure/flow curve, meaning flow is dropping off, the pump is working harder, etc. Depending on the pump we are working with we may get near the pressure bypass. And, as stated in point 2 above, we are asking more of the pump for no reason. We have other, easier, options. Injector duty cycle is barely breaking into the 60s. There is no need for increased base fuel pressure beyond the tried and true 43.5 psi.

@Tony J As for the knock you are seeing. On 91 pump and 15.5 deg advance with 6500rpm/21 psi (first knock event during pull) I would not be surprised to see 0.4. That being said, 0.4 would never bother me and I wouldn't make a change to correct it personally.

Additionally. Is your base fuel pressure set to the 37 psi you used in the Global Fuel calculator setting? If the answer is no, I would redo the calculator with your actual base fuel pressure and make that global % change.

As for fixing the fueling during WOT. You have two things to change. Adjust the Openloop Max/MinOct tables to demand 10.7-11.0 in the load regions. Your car is demanding a value you won't want to run as shown by the very rich AFREst values and you are not hitting the demanded values either meaning you will need to use the VE table to get the values to line up (WBFactor closing in on 0% during WOT). I know you are demanding 100 peak already, but those values are also scaled by the global fuel %. You can make the car work with VEs above 100. People will say that means you have an incorrect fuel calibration, which is true, but that doesn't make the car run any worse. I was pro tuned by Ricky at Rix Racing, a well established tuner here, on his dyno, and my peak VE on the table was 106. Car ran perfect. Long term get your VE table to 100 peak to get accurate airflow readings and all that, but it isn't required to get a running, safe tune. NOTE: When you adjust the open loop demand tables up, your car will lean out. You are asking for 9.3 now and getting 10s+. When you adjust it to ask for 10s it will lean out further. I would make a corresponding VE table change based on the WBFactor at the same time you are adjusting the open loop AFR demand.

As with all things tuning, there are many paths to the destination. My opinions are above. Make decisions as you see fit based on your research and experimentation with your car. At least you seem to be at a point doing pulls is safe and consistent allowing you to really start diving into the WOT section without too much worry.
 
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Tony J

Proven Member
32
6
Oct 2, 2020
Belleville, ON_Canada
I, as we discussed above, disagree with the adjusting the FPR approach here:

1. WB Factor is not consistent during the pull, it swings from 10% to nearly 20%. That means a global change will not correct all of the fueling disparities.

2. Adjusting global fuel % will result in an identical response as you are suggesting with the regulator change. It will move all fuel everywhere. And the cruise section right at the beginning doesn't need nearly as much adjustment as during WOT. Why mess up cruise to not fix WOT?

3. As we increase base fuel pressure, and thus the rising rate fuel pressure peak, we are moving the fuel pump farther and farther up its pressure/flow curve, meaning flow is dropping off, the pump is working harder, etc. Depending on the pump we are working with we may get near the pressure bypass. And, as stated in point 2 above, we are asking more of the pump for no reason. We have other, easier, options. Injector duty cycle is barely breaking into the 60s. There is no need for increased base fuel pressure beyond the tried and true 43.5 psi.

@Tony J As for the knock you are seeing. On 91 pump and 15.5 deg advance with 6500rpm/21 psi (first knock event during pull) I would not be surprised to see 0.4. That being said, 0.4 would never bother me and I wouldn't make a change to correct it personally.

Additionally. Is your base fuel pressure set to the 37 psi you used in the Global Fuel calculator setting? If the answer is no, I would redo the calculator with your actual base fuel pressure and make that global % change.

As for fixing the fueling during WOT. You have two things to change. Adjust the Openloop Max/MinOct tables to demand 10.7-11.0 in the load regions. Your car is demanding a value you won't want to run as shown by the very rich AFREst values and you are not hitting the demanded values either meaning you will need to use the VE table to get the values to line up (WBFactor closing in on 0% during WOT). I know you are demanding 100 peak already, but those values are also scaled by the global fuel %. You can make the car work with VEs above 100. People will say that means you have an incorrect fuel calibration, which is true, but that doesn't make the car run any worse. I was pro tuned by Ricky at Rix Racing, a well established tuner here, on his dyno, and my peak VE on the table was 106. Car ran perfect. Long term get your VE table to 100 peak to get accurate airflow readings and all that, but it isn't required to get a running, safe tune.

As with all things tuning, there are many paths to the destination. My opinions are above. Make decisions as you see fit based on your research and experimentation with your car. At least you seem to be at a point doing pulls is safe and consistent allowing you to really start diving into the WOT section without too much worry.
I like everything you're saying. I've been told to change target afrs... I can only remember so much the main thing is to keep things safe. I've never heard of anyone blowing up for toor rich .... I feel like my cruise is really dialed in.. my fuel pressure in ecm link is actual pressure at fpr with pump turned on vac line pinched.

I'd like 400 hp. If link is accurate at 21 psi I'm around 362 ish rn. I'm looking to squeeze a few more psi out of the turbo without adding meth....
 

llxkevinxll

10+ Year Contributor
489
231
Jan 29, 2012
Milwaukee, Wisconsin
I like everything you're saying. I've been told to change target afrs... I can only remember so much the main thing is to keep things safe. I've never heard of anyone blowing up for toor rich .... I feel like my cruise is really dialed in.. my fuel pressure in ecm link is actual pressure at fpr with pump turned on vac line pinched.

I'd like 400 hp. If link is accurate at 21 psi I'm around 362 ish rn. I'm looking to squeeze a few more psi out of the turbo without adding meth....

You can go so rich as to wash down cylinder walls, thin the oil and a multitude of other bad things. But from what I understand you need to be really really rich. So there is a lower limit but nothing you should need to worry about short term.

Adjust AFR demand to be more "normal" for pump gas. 10.7-11.0 is typical for our cars and you will see those numbers plastered in guides and posts on this forum.

As for power numbers, I am unsure ECMLink HP will be very accurate right now as the calibration still needs work. Of course it is always limited by the fact that it is a calculation but it will likely be way off right now. Also note, there are options when right clicking the Horsepower signal. Car weight, gear ratios, drivetrain loss factor etc. that will affect what ECMLink shows for HP.

Read this guide if you haven't.
 
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Stapl3

15+ Year Contributor
1,597
167
Oct 27, 2004
MI, Michigan
It will move all fuel everywhere. And the cruise section right at the beginning doesn't need nearly as much adjustment as during WOT. Why mess up cruise to not fix WOT?
It will not move fuel as much with cruise and idle as you think. I do not know why, but in the real world it just doesnt.

My method will have to do cruise and idle maybe a couple times. There is a little chasing your tail. But why would you not want the fuel system calibrated perfectly? What other method is there aside of all that stuff lining up perfectly at VE?

As we increase base fuel pressure, and thus the rising rate fuel pressure peak, we are moving the fuel pump farther and farther up its pressure/flow curve, meaning flow is dropping off, the pump is working harder, etc. Depending on the pump we are working with we may get near the pressure bypass. And, as stated in point 2 above, we are asking more of the pump for no reason. We have other, easier, options. Injector duty cycle is barely breaking into the 60s. There is no need for increased base fuel pressure beyond the tried and true 43.5 psi.

Well then change the global. Either way, he's lean.

And to sidebar on that. I run as high base fuel pressure as I can on all my cars. One of my cars is at 80psi base fuel and it's absolutely fantastic. Maybe the best thing I've ever done with a DSM. The injectors behave so differently, the response and personality of the car is incredible. Never had an issue doing this, only benefits.

As for fixing the fueling during WOT. You have two things to change. Adjust the Openloop Max/MinOct tables to demand 10.7-11.0 in the load regions.

Sorry but l0l here. The car is demanding mid 9s and outputting mid 10s. So you think the output will remain in the mid 10's if the table is changed? What is the point of the table then? Its like I said above having an alarm clock 1 hour 18 minutes off and forever factoring that in. It's nonsense. Any of my cars I've tuned, I can put 9.0 or 15.0 in the cell and that is exactly what will happen. No guessing, no games.

People will say that means you have an incorrect fuel calibration, which is true, but that doesn't make the car run any worse. I was pro tuned by Ricky at Rix Racing, a well established tuner here, on his dyno, and my peak VE on the table was 106. Car ran perfect.
So, it's wrong. Airflow is overinflated, marginally, but inflated to make up for an incorrectly calibrated fuel system. Numbers you put on the target af ratio table in DA won't equal the output as well as it should, and the values logged like TQ and HP will be wrong. Is it good enough to drive, of course. But I don't see a point in going 95% of the way there, unless you're limited to 3 pulls or an hour of screwing with the car.
 

llxkevinxll

10+ Year Contributor
489
231
Jan 29, 2012
Milwaukee, Wisconsin
Sorry but l0l here. The car is demanding mid 9s and outputting mid 10s. So you think the output will remain in the mid 10's if the table is changed? What is the point of the table then? Its like I said above having an alarm clock 1 hour 18 minutes off and forever factoring that in. It's nonsense. Any of my cars I've tuned, I can put 9.0 or 15.0 in the cell and that is exactly what will happen. No guessing, no games.

Copying from my post above, I think you missed some things I said.
"NOTE: When you adjust the open loop demand tables up, your car will lean out. You are asking for 9.3 now and getting 10s+. When you adjust it to ask for 10s it will lean out further. I would make a corresponding VE table change based on the WBFactor at the same time you are adjusting the open loop AFR demand."

So, it's wrong. Airflow is overinflated, marginally, but inflated to make up for an incorrectly calibrated fuel system. Numbers you put on the target af ratio table in DA won't equal the output as well as it should, and the values logged like TQ and HP will be wrong. Is it good enough to drive, of course. But I don't see a point in going 95% of the way there, unless you're limited to 3 pulls or an hour of screwing with the car.
Copying again from above, as you must have missed it:
"Long term get your VE table to 100 peak to get accurate airflow readings and all that, but it isn't required to get a running, safe tune."

Also, do we really believe actual peak VE is 100%? VE, volumetric efficiency, is a ratio of air volume sucked (rammed in by a turbo in our cases) into a cylinder and the empty volume of the cylinder. When I am running a bunch of boost I better not be only 100% volumetrically efficient on my 2L or I am going to get walked by everyone. Turbo cars have true VE that goes way beyond 100%. We are cramming a ton more air than 500cc into each cylinder each revolution. These numbers being calibrated to 100% peak is our goal to make everything clean and well calibrated. But those numbers are offset by a bunch of other numbers. All of which can add up to not 100 and still have a perfectly tuned car. Getting peak VE to 100% on the table is, in my mind, not even close to step 1. We are on step 1 here.
 

Stapl3

15+ Year Contributor
1,597
167
Oct 27, 2004
MI, Michigan
Copying from my post above, I think you missed everything I said.
"NOTE: When you adjust the open loop demand tables up, your car will lean out. You are asking for 9.3 now and getting 10s+. When you adjust it to ask for 10s it will lean out further. I would make a corresponding VE table change based on the WBFactor at the same time you are adjusting the open loop AFR demand."


Copying again from above, as you must have missed it:
"Long term get your VE table to 100 peak to get accurate airflow readings and all that, but it isn't required to get a running, safe tune."

Also, do we really believe actual peak VE is 100%? VE, volumetric efficiency, is a ratio of air volume sucked (rammed in by a turbo in our cases) into a cylinder and the empty volume of the cylinder. When I am running a bunch of boost I better not be only 100% volumetrically efficient on my 2L or I am going to get walked by everyone. Turbo cars have true VE that goes way beyond 100%. We are cramming a ton more air than 500cc into each cylinder each revolution. These numbers being calibrated to 100% peak is our goal to make everything clean and well calibrated. But those numbers are offset by a bunch of other numbers. All of which can add up to not 100 and still have a perfectly tuned car. Getting peak VE to 100% on the table is, in my mind, not even close to step 1. We are on step 1 here.
Peak VE doesn't mean VE is at 100. It means the value used on the table is 100.

Getting those 3 to line up at peak VE has to be step 1, because everything revolves around that. If the fuel system is not calibrated, then everything is side-step and robbing peter to pay paul. It's just all wrong.

When you adjust the open loop demand tables up, your car will lean out. You are asking for 9.3 now and getting 10s+. When you adjust it to ask for 10s it will lean out further.
When I adjust the tables on my car, I get EXACTLY what I type in. Nothing else. There is no leaning event as you suggest. I have never experienced that.
And that is really the crux of the game. All these physical and non physical adjustments boil down to the tables being completely accurate. I want X timing and X afratio at this moment and I either get it or not. That's it really.
When you adjust it to ask for 10s it will lean out further.
Well, yeah. But if you ask for 10s and are now getting 11s, your shit is skewed and wrong. If you get anything other than the value on the table, then your shit if miscalibrated.

Hmmm to adjust global or adjust fuel pressure? 🤔🤔🤔
They are one in the same. I personally do the afpr. Doesn't matter.
 
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llxkevinxll

10+ Year Contributor
489
231
Jan 29, 2012
Milwaukee, Wisconsin
When I adjust the tables on my car, I get EXACTLY what I type in. Nothing else. There is no leaning event as you suggest. I have never experienced that.

Well, yeah. But if you ask for 10s and are now getting 11s, your shit is skewed and wrong. If you get anything other than the value on the table, then your shit if miscalibrated.
When I ask for 9s and get 10s, and change it to ask for 10s without changing anything else, I am not going to magically get 10s again. If you lean out the AFR demand tables you will lean out the actual AFR, regardless of if the car is well calibrated or not. I am confused by your statement here. Even your perfect car would get leaner when asking for a leaner AFR. What would be the purpose of the table otherwise? We all know his VE table and global needs work, which everyone has stated. But he has demand tables asking for 9s which no one with a DSM is running on pump gas. Those tables need to change to something reasonable along with adjusting everything else to bring the demand vs. actual disparity down to near 0. The AFR demand table is a set and forget. Make it reasonable, target normal values, and dial it in from there.
 

Stapl3

15+ Year Contributor
1,597
167
Oct 27, 2004
MI, Michigan
When I ask for 9s and get 10s, and change it to ask for 10s without changing anything else, I am not going to magically get 10s again. If you lean out the AFR demand tables you will lean out the actual AFR, regardless of if the car is well calibrated or not. I am confused by your statement here. Even your perfect car would get leaner when asking for a leaner AFR. What would be the purpose of the table otherwise? We all know his VE table and global needs work, which everyone has stated. But he has demand tables asking for 9s which no one with a DSM is running on pump gas. Those tables need to change to something reasonable along with adjusting everything else to bring the demand vs. actual disparity down to near 0. The AFR demand table is a set and forget. Make it reasonable, target normal values, and dial it in from there.
I am separating calibrating from tuning. I don't care at all if his target ratio is 9.4 or 11.4. My only interest is calibrating it so what actually occurs is what is actually typed in there.

Type 10.7 in there if you want. But if it's not 10.7 coming out of the engine, then we're exactly where we're at now; it being wrong.

And on top of that, I think what you're suggesting is dangerous, as right now the car is seeking mid 9s and getting mid 10s, so you now are saying to put the values in the table at 10s.... then he would be outputting in the upper 11s?
 

llxkevinxll

10+ Year Contributor
489
231
Jan 29, 2012
Milwaukee, Wisconsin
I am separating calibrating from tuning. I don't care at all if his target ratio is 9.4 or 11.4. My only interest is calibrating it so what actually occurs is what is actually typed in there.

Type 10.7 in there if you want. But if it's not 10.7 coming out of the engine, then we're exactly where we're at now; it being wrong.

And on top of that, I think what you're suggesting is dangerous, as right now the car is seeking mid 9s and getting mid 10s, so you now are saying to put the values in the table at 10s.... then he would be outputting in the upper 11s?
Agreed. I noted that exact fact in a note to him directly and copied it a second time in a response to you. Here it is again for a third time:

NOTE: When you adjust the open loop demand tables up, your car will lean out. You are asking for 9.3 now and getting 10s+. When you adjust it to ask for 10s it will lean out further. I would make a corresponding VE table change based on the WBFactor at the same time you are adjusting the open loop AFR demand."

He currently has WBFactor values he can use to modify the VE table. The ECU is indicating how far off it is already. 10% leaner than demanded climbing to 19% leaner than demanded at one point in that log. This will push VE values beyond 100% of course and the global fuel % would need to be used to rescale the VE table back to the holy grail of 100% peak. If desired.
 

jdxnc

10+ Year Contributor
387
342
Sep 15, 2009
Stanstead, Vermont
My target is not 9.3, I believe I need to change my max octane tables

This is what I'm told anyways.

Are you assuming my target is 9.3??
You ARE targeting 9.3. Fix your tables before going further.

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