Program to generate VE equations

[Bluecat]

New version to download, link in first post reflects the changes.

Changed generation routines, up to 30% better matches.

Fixed a bug that wasn't let the constant coeffecients go negative. Should really help the generation routines. Suppised they worked as good as they did.

Added a Manual button that lets you do the zones by hand. Not really for anything other than my debugging, so don't harp on me if things don't work.



If anybody could even take a half assed table that thier car will run on and go log it including the "GM Volumetric Efficiency (raw VE value)" pid. That way I can see if the pcm will take generated values properly. If it will then the only thing to work on is making better matches, and I can do that with test data sets and no test car.

Heres a test VE table that I generated with a stone stock LS1 car after being tuned.


Here is the VE table that the program approximates to and that a forumula based car should run off of.


Here is the difference between the two.


I'm content with the results, I just need to know if it works in the field.

[deanm11]

Understood, thanks for the explanation. The reason my format was to that granularity was that my histogram was to that granularity, provided by carneb.

The units are fine, but the standard LS2 VE table is a 17x17 grid with the RPM from 400 to 6800 in 400 rpm increments and the MAP from 15 to 105 in 5.625 KPA increments. If you have any questions just checkout some of the table.txt's. You can see LS1's and LS2's not only use different numbers, but the axis are swapped.

Since the Non-Table format dosen't actually have any standard boundries (the formulas would yield a number for 10000rpm and 200kpa if thats what you plug in), thier is no true format. But since HPtuners kept the histograms for these type vehicals in the last LS2 format used with a VE table, thats the way I support it. Unless you use the same format as the histograms in the scanner, the histograms are kinda useless.

[Bluecat]

Let me crawdad a minute here. Early on, when these computers first came out, I downloaded a few hpl and hpt files off the internet to check them out. I had though that when you went to a histogram that was formated primary ve, that they had wrote a code work around and just told it to use the LS2 format since that vehical didn't really have a VE table.

Appartly on the logs I was looking at someone had manually setup the table for the histogram or I was just plain looking at something else and screwed up. Anyway after reviewing the the logs from those vehicals that I've done, there is no automatic selection of a VE table. You have to manually setup the axis for rpm & map and fillout the formating by hand. Sorry for spouting out false information.

In light of that I can add support for any style VE table you guys would like to work with. Is the huge 46x39 15-105 kpa in 2 kpa incements / 400-8000rpm in 200 rpm increments what you guys are used to working with?

[EC_Tune]

As it's set up, can you do a 2 bar cal with it by changing the boundaries and "creating" a VE table for it?

[redhardsupra]

As it's set up, can you do a 2 bar cal with it by changing the boundaries and "creating" a VE table for it?

or 1.34bar if that's what's more suiting! that's the genius of the response surface based VE tables.

[EC_Tune]

Exactly.

However no point in going over 255 Kpa (yet) as the E38/E67 PCM(s) don't support >255Kpa or greater than 4096 according to Chris.

[Bluecat]

I just updated the files again. Adding support for the bigger "Carneb" table. Let me know if its right or I need to change it.

Yes I can add support for a 2bar table format. I'll do that tonight.

[carneb]

When I first set up my spreadsheet I thought that the more data points per zone the more accurate the results would be. Thats why I went with such a large table. It would be interesting to see if this is the case or if the LS2 style table does the job just as well.

I made a version of my spreadsheet to look at a 2 bar VE table. Using the standard coefficients and zone boundaries it's not pretty!

[Bluecat]

2 Bar added. Files updated. Autozone boundries for the map in 2Bar mode default to 43,71,100,133,166.

Were getting a lot of bells and whistles on this thing to have still not verified its. Any logs I can look at yet?

[Bluecat]

You can definatly tell more about it with the bigger table details, but the way my program works the resolution of the table you feed it is kinda irrelavent. It breaks the zone down into certain size slices reguardless of the table resolution its trying to match. I will say that the larger tables has show me some places that the routine could use some work just because you can see the shape in more detail.

[Billf6531]

This is interesting stuff. Does it have any relevance to tuning an LS1?

[Bluecat]

Nope.

[EC_Tune]

Didn't get a chance to work with it today. I'll see what I can come up with tomorrow. I have an 05 Vette going on the dyno in the morning but that already has a VE table. Also have a supercharged 06 in the shop as well. That may be my candidate...

[Bluecat]

Updated yet again. Added the ability to stop the generation process.

Originally I just wanted to be able to get a decent SD tune running underneath the MAF so you wouldn't have to turn the high rpm disable down to 400 and kill the SD. Since it looks like most people are wanting to go pure SD or FI SD, I increased the persicion a lot. It slows it down quite a bit so now the speed slider bar starts towards the middle. So when you need to "go for the gold", slide it all the way back to the left.

[BADSZ28]

This is great. Thanks for your time on this. One question; if you create a VE in % using the program and then modify the VE in %, will the program recognize and properly back calculate from % values? Or do you have to convert to raw numbers from %?

[Bluecat]

The table format and ve option applies to both generating the tables and reading them back in. If you make it in VE format, just make sure you still have the box checked when you read it back in.

Don't forget to make sure that the cylinder volume at the bottom of the equation.txt is right for your engine so that your dealing with realistic VE%numbers.

[Bluecat]

I case anyone is still concerned, I used it on a 07 C6 A6 today and it worked flawlessly. As far as I'm concerned its ready to go.

[deanm11]

I case anyone is still concerned, I used it on a 07 C6 A6 today and it worked flawlessly. As far as I'm concerned its ready to go.

What kind of mods did the C6 have? Curious to see the final VE and mod list to compare, especially if it was a headers car like mine.

[Bluecat]

Long tubes, High flow cats, and a CAI.

I started from a VE table I had made for a LS2 GTO with the same mods but without cats. It was pretty close the first try, but the mid range was very lean. Ended up making a table that was odd because it was so flat. I'll post it up next time I transfer stuff from my laptop to this computer.

[deanm11]

Long tubes, High flow cats, and a CAI.

I started from a VE table I had made for a LS2 GTO with the same mods but without cats. It was pretty close the first try, but the mid range was very lean. Ended up making a table that was odd because it was so flat. I'll post it up next time I transfer stuff from my laptop to this computer.

Great, would appreciate it. I'll put mine up as well.