Changing spark table axis to MAP values

[Goinbyyabig]

Can I change from airmass to a map value in the spark tables? I can't convert the airmass values to input an intelligent amount of advance. Not sure how to approach this, or how you guys are doing it. 2 bar SD E38 setup, see tune attached.

[jjs]

Can I change from airmass to a map value in the spark tables? I can't convert the airmass values to input an intelligent amount of advance. Not sure how to approach this, or how you guys are doing it. 2 bar SD E38 setup, see tune attached.

As far as I know, you can only change the units.

[Goinbyyabig]

I emailed HP and Bill responded that 90% of their software is this way. He also said that if I'm looking for some "free tuning advice" that I should come here and ask. That kind of shocked me as he has been tremendously helpful with other issues in the past. So, what's the secret to turn a mass air flow calculated number into something I can make sense of and fill my timing tables with something halfway intelligent? I made a new table on Scanner that shows RPM vs. Map for axis and Grams/cyl on the chart. I think I roll over into boost around .72G or so. Idles around .15.... But it still feels like I'm flying blind. Apparently I'm not "getting it".... any thoughts?

[jjs]

I emailed HP and Bill responded that 90% of their software is this way. He also said that if I'm looking for some "free tuning advice" that I should come here and ask. That kind of shocked me as he has been tremendously helpful with other issues in the past. So, what's the secret to turn a mass air flow calculated number into something I can make sense of and fill my timing tables with something halfway intelligent? I made a new table on Scanner that shows RPM vs. Map for axis and Grams/cyl on the chart. I think I roll over into boost around .72G or so. Idles around .15.... But it still feels like I'm flying blind. Apparently I'm not "getting it".... any thoughts?

I changed my histo to match the timing tables. I changed the histo to display error from cylinder airmass in grams like the timing table and use that for correction.

[10_SS]

I changed my histo to match the timing tables. I changed the histo to display error from cylinder airmass in grams like the timing table and use that for correction.

Im pretty sure this is how everyone does it. Make the Scanner tables match the Editor tables for pretty much anything you want to edit. I think it makes sense that GM did it this way. The confusing alternative is to have two spark tables in the OS, one that uses MAP, then one that uses calc. airflow. The way it's setup now it uses one table. That is why they say start with your VE table, get that squared away then move on to the spark table.

[Goinbyyabig]

I changed my histo to match the timing tables. I changed the histo to display error from cylinder airmass in grams like the timing table and use that for correction.

I'm not sure I follow that. if I set up a histogram to match the timing table, what error can I see if there's no "desired spark" as opposed to what shows up in the histogram as actual? Or would I compare the airmass table reading to the Map reading on the graph to see what the timing actually is at, say, 140 or 180 KPA? But then the airmass error doesn't make sense. Sorry guys, I'm not with you yet. Thanks for the responses, though!!

I can't see how, with a custom OS, that the calculated airmass can't happen after the spark table is established, to feed the rest of the system relying on airmass numbers that aren't there due to MAF deletion. I know it's not going to happen. Just seems so much more difficult to manipulate.

[10_SS]

I'm not sure I follow that. if I set up a histogram to match the timing table, what error can I see if there's no "desired spark" as opposed to what shows up in the histogram as actual? Or would I compare the airmass table reading to the Map reading on the graph to see what the timing actually is at, say, 140 or 180 KPA? But then the airmass error doesn't make sense. Sorry guys, I'm not with you yet. Thanks for the responses, though!!

I can't see how, with a custom OS, that the calculated airmass can't happen after the spark table is established, to feed the rest of the system relying on airmass numbers that aren't there due to MAF deletion. I know it's not going to happen. Just seems so much more difficult to manipulate.

This would not be reporting error, it will just be commanded spark at whatever RPM and Airflow. Not error.

I see what your saying now, you want difference from what's in your High Octane spark table and what the scanner says. Not sure how to do that unless you paste it into Excel which you could do then subtract the two values but would be an extra step. As far as the Airflow vs MAP, once I realized the airflow axis works the same way, just set scanner up and forget about it. Use MAP for fuel and airmass for spark. Not really sure why GM did it that way but they do, probably because it's primarily designed for Airflow from MAF and VE Coefficients, by converting to the 2Bar they restored the MAP table and got rid of VE Coefficients which separates it from how it was originally setup. We have to remember GM originally setup the OS not with a VE table, but VE Coefficients, so we are lucky to even have the older style MAP table.

Actually another thing I think your asking for is how Megasquirt Tunerstudio is set up. The scanner program can scan just like HPT scanner does, BUT one main difference is the scanner and also load the TUNE file so it can overlay tune data and location of say the fuel and spark cells in real time both when running and when reviewing the log so you can see knock on the plot and it will show what cell it's in to the right, you can edit that cell to update that way. Much easier.

HPT could add this type of editing to the scanner, it would'nt have to be Real Time Tuning, just real time editing, just the scanner to tune file linking.. that would be awesome. It's pretty good the way it is now though with the histograms/graphs or whatever they are called.

[Goinbyyabig]

10_ss, thanks for the detailed response. I should clarify, I was not trying to see error in the scanner. I was only responding to jjs saying that he set it up to show error in the scanner.

My point is, basically, if there is no MAF anymore with the 2 bar OS, and the ecu will be calculating the MAP input to determine a cylinder airmass number, why can't we simply use the MAP as an axis for desired spark? I realize that's not how it's set up, and will not be changing, but still...

Maybe I can set up a table to show calculated airmass with MAP and RPM as the axis? Therefore showing me where to adjust the timing tables? Hmmmm..... There has to be a way to convert an airmass number into an absolute pressure number in the manifold. So it's possible to know what the airmass is at, say, 8 lbs of boost at 4000 RPM, etc. Maybe I'll try to do that.

Sorry, I'm used to standalone systems; so much simpler and easy to use. But I'd love to understand how guys are doing this.

[10_SS]

10_ss, thanks for the detailed response. I should clarify, I was not trying to see error in the scanner. I was only responding to jjs saying that he set it up to show error in the scanner.

My point is, basically, if there is no MAF anymore with the 2 bar OS, and the ecu will be calculating the MAP input to determine a cylinder airmass number, why can't we simply use the MAP as an axis for desired spark? I realize that's not how it's set up, and will not be changing, but still...

Maybe I can set up a table to show calculated airmass with MAP and RPM as the axis? Therefore showing me where to adjust the timing tables? Hmmmm..... There has to be a way to convert an airmass number into an absolute pressure number in the manifold. So it's possible to know what the airmass is at, say, 8 lbs of boost at 4000 RPM, etc. Maybe I'll try to do that.

Sorry, I'm used to standalone systems; so much simpler and easy to use. But I'd love to understand how guys are doing this.

I guess I don't understand what problem your having. You adjust the timing tables as they are right now. RPM vs Airmass. Setup Scanner to match what your editor Spark column has, most likely RPM vs Spark Airmass like jjs said. This is how it's done.

If your not seeing the timing that you have in the numbers in High Octane table being reported by scanner in the same cells, then you have other problems like maybe Knock Learn is high so it's blending from the Low Octane table, or you have many of the other Spark Modifiers adding or subtracting timing. None of this has to do with the name of the axis label that GM/HPT is using (in this case, Airmass instead of MAP kPa). If you could change just the name of the axis you could make it BEER FLOW for all I care, just make sure Editor and Scanner have the same channel/PID for that axis and it will report the correct number.

So my High Octane table in editor is RPM on top, and Spark Airmass (g) going down the left side. In scanner I have this setup the same way, but I think it's called Cylinder Airmass (g) in scanner. Is that maybe where the confusion is?

[Goinbyyabig]

The simplest way I can answer is this: I can't determine how much manifold pressure equates to XXX airmass number. Therefore, I don't know where on the map I'm at 5 lbs or 20. Does that make sense?
I realize that there's a spark table that I can set up for base desired spark, high and low octane, before any multipliers, etc.

My scanner has a table preset that shows what the current advance is, already. But it uses MAP as the axis down the left side. It came that way, and does display a value.

For example, if I want to convert kpa to boost, it's simple, 105 is atmospheric pressure, 210 is about 15 psi. I can't convert airmass numbers in such a manner.

[10_SS]

The simplest way I can answer is this: I can't determine how much manifold pressure equates to XXX airmass number. Therefore, I don't know where on the map I'm at 5 lbs or 20. Does that make sense?
I realize that there's a spark table that I can set up for base desired spark, high and low octane, before any multipliers, etc.

My scanner has a table preset that shows what the current advance is, already. But it uses MAP as the axis down the left side. It came that way, and does display a value.

For example, if I want to convert kpa to boost, it's simple, 105 is atmospheric pressure, 210 is about 15 psi. I can't convert airmass numbers in such a manner.

oh, that's easy. You need to add the MAP channel in your channels list, make sure it shows a value, then just make sure your selecting the correct MAP channel as that axis in the graphs... best way to do that is make sure you select "show only parameters that are backed by channels" when your in the Charts Paramaters setting the axis up. Why they don't make that default, I don't know.
Charts can be configured on any old log file if you have the required channels being logged. That part can be confusing.

I just did it on an old log of mine since I had the map channel being logged. Here's a couple pics, maybe that will help.

But, that will not be usefull in tuning in the editor since the MAP channel isnt on the Spark axis in editor, Airmass is. Right above my "Spark Adv vs MAP" I have the "Spark Adv vs Airmass" which correlates to the Editor Spark tables so I know exactly where to adjust timing.

Spark_MAP.PNG

Spark_MAP 2.PNG

[10_SS]

Further, if you just want to see how they correlate, you put MAP on one axis, then Cyl Airmass on the other and use Spark as the data as shown below.

So now I know I enter boost around 0.80 g/cyl Airmass (or Cyl Airmass). This is data from the entire drive so data is pretty wide.

Spark_MAP vs Cyl Airmass.PNG

[Goinbyyabig]

Thank you for taking the time to offer intelligent replies; I appreciate it, greatly.

My preloaded spark table shows map vs. RPM and does fill up with actual, final spark data. That's right where I was frustrated. If they offer that as a preloaded table, how do I use it?? Hahahaha. The second table you posted is interesting. I used some of my datalogs to compare map to airmass on the charts and believe I'm crossing into boost around .76 so I wasn't too far off in that. I wonder if I can make a MAP vs. RPM table with airmass as the data. That should answer my questions, completely.

I saw a video about setting up tables and have been using the gear icon with the green checkmark. I agree, it's handy. Thanks again. Tine to go experiment, I think.

[mightyquickz28]

Thanks for these posts. I've setup the SparkAdv_Map PID now. But how does one set the Cylinder AirMass Grams in the editor to correlate to a 3 bar? I see above in your example, your PID goes to 136, whereas my 0411 3 bar OS stops at 120 in both the editor and the scanner. Is there a way to extend the cylinder Airmass rows in the editor to be commensurate with the 3bar so I can see what spark is administered at a given RPM/Airmass axis? Or is it an ECM limitation? I've been running the 3bar SD tune for the past 3 years and it starts/runs great on my 5.3 PT7675 turbo'd 96 Z28. I drive around most often with my laptop running the scanner to see how things are doing and tweaking the tune if necessary. Thanks for all your assistance!

[Goinbyyabig]

I'm back to struggling with this tuning based on airmass situation, lol. I have been driving the vehicle and cautiously adding boost as I go. I am up to about 7 psi and have almost reached the end of the airmass resolution on the main high spark table. 140 kpa shows 1.26 g/s airmass, and the spark table only goes to 1.36. I'm confused what I will use beyond the limits of this table for spark control. I don't see a "boost timing" table anywhere, or an adder based on map numbers. Can anyone offer some insight?

[10_SS]

I'm back to struggling with this tuning based on airmass situation, lol. I have been driving the vehicle and cautiously adding boost as I go. I am up to about 7 psi and have almost reached the end of the airmass resolution on the main high spark table. 140 kpa shows 1.26 g/s airmass, and the spark table only goes to 1.36. I'm confused what I will use beyond the limits of this table for spark control. I don't see a "boost timing" table anywhere, or an adder based on map numbers. Can anyone offer some insight?

Whats your MAF HZ at? That's the important part. If you have 0-15,000 and your only at 11,000 at WOT your ok. You should be able to increase your 1.36 g/s value on that axis much higher if you need, right click the spark airmass axis, choose Row Axis/Edit. Bump up the last cell to 1.5 or whatever you want, then interpolate between that cell and a couple before it. You will have to move your spark values to match though. But, you may not need it. Whatever timing is in the last row will hold for any value over that.

[Chris@HPTuners]

I'm back to struggling with this tuning based on airmass situation, lol. I have been driving the vehicle and cautiously adding boost as I go. I am up to about 7 psi and have almost reached the end of the airmass resolution on the main high spark table. 140 kpa shows 1.26 g/s airmass, and the spark table only goes to 1.36. I'm confused what I will use beyond the limits of this table for spark control. I don't see a "boost timing" table anywhere, or an adder based on map numbers. Can anyone offer some insight?

on the E38 you can edit the spark axis values to whatever you want. Click on the underlined Cylinder Airmass (g) text and the axis table will open (any underlined tables like this can be opened and edited). Also the the table will hold the uppermost value if the axis range is exceeded. So if your airmass exceeds 1.36 it will use the 1.36 row (unless you change the axis values).

[beau.]

I used a user-define math parameter to define boost within the software. We define boost by subtracting Barometric Pressure from your upgraded MAP sensor (2, 2.5, 3bar) reading. Then I plotted the newly user-defined math for boost on the spark table x and y axes. I referenced the high boost values on the histogram to adjust my spark table in my tune line by line. Pics attached.

Boost Math - 3 bar.jpg
Boost to Airmass histogram.jpg
Boost to Airmass graph.jpg