ChrisB

You are getting the 35-88 values becuase those are in units of percent! Since NoGo figured out the full scale scaling of 3000 you can set that in the program - there is a dialog box titled something like "full scale value" - set that to 3000. The you should get LS1 style values.

I know the operation is still a bit clunky, but I haven't had much time recently to work on it. I will see if I can whip up a VE only little app that will be much simpler.

blinksz06 brought up a good point - if the software isn't recognizing the header titles then you will get errors - I haven't checked this out with efilive v6 yet - but if the header titles are different it's just a matter of adding them in (which you can do through the software, or with notepad and opening the xml config file).

JxxxOxxxE

iTrader: (1)

Ok, cool. I got it to work to an extent, I think. So I exported my stock VE table to a file, then made sure the program would load everything right, changed the full scale value to 3000, and had it on the "calculated VE values." This seemed to want to make a hump in the middle of the table with everything else staying flat..here is a screenshot..



And when I select "table from PCM," this gives the percentages I should use compared to my loaded VE table? Is that correct. That would seem to make some of these a little low wouldnt it?



So should I just let it copy everything over now? Will it be making changes to hit the target L-Trim value too? Thanks in advance...

ChrisB

uncheck the "scale pcm table as percentage" value and it will be in "ls1 edit" units.

The first graph is the correct one - the reason you have a hump in the middle is because those are the only cells that you have data for - right now it just defaults to 0 if no data is present.

You can just work with that data and extrapolate it yourself - or try and get a log file where you hit more of the data cells.

I am working on a automatic interpolation for the entire table, but that will still be awhile. Right now you pretty much need to get as much data as you can then "hand smooth" it as best you can for the cells you don't have data for.

66ImpalaLT1

Chris what is the limit on log file size?

I'm getting an error trying to import a file of 115k lines.

billc5

iTrader: (1)

I will try to dumb it down to my level, and see if I have got this VE defintion straight. In context remember that I have a roots blower

VE is: Input Air/used air, used air is the cylinder volume. the unused air is that which flowed through due to overlap with the valves openning.

SO if I improve the Flow Through with say Headers then the value of the VE number should increase because there is now more wasted air(more input air), since we have the same fuel/RPM I should expect a richer AFR condition(the MAF sees more air and adds fuel accordingly). Because there is more wasted air in the exhaust the O2 sensors think we are lean and adds fuel, I would speculate that at closed loop the real ARF is now richer than the EPA requirement and clean air becomes harder to achieve. Anyone know how to calibrate the expected O2 for the 4 sensors??? hmmmm I didnt think so. Does the VE table have any responsibility for this?? hmmmm hope springs eternal.


The only benefit here from improved flow would be for the guy who I paid to install the Heasders and Xpipe. If I retune the engine I can get back some of the power with additional timing and less fuel in Power Enrichment, I have no way to tune closed loop, oops!, This has been my experience.

I have managed to calculate the VE using EFI_Live and the stock C5 VE table seams to be at least 10 to 20% low everywhere which is consistent with what I would now expect from the addition of the new Blower Intake Manifold and Headers.

I would also assume that the Magnuson Blower intake manifold is not as tuned as stock and therefore would lower the MAP at closed loop and heaven only knows what happens at Open Loop since the MAP OD's above 104.

SO the $million questions are should I increase the VE table everywhere and is there a benefit? given that the current performance is above my expectations, and will the headers allow me to increase the boost for more power when I otherwise could not?

Please let me know if this is seated in reality or should I be talking to Disney?

JxxxOxxxE

iTrader: (1)

Thanks chris. Is there a certain way I should go about trying to hit all the cells...? The data log I used just to get the values above only had about 4900 lines of data, which equates to about 20-25 minutes of driving for me...

So say I get more data, and hit more of the cells, then I just go in, and try to make the graph smooth, by entering values close to the ones I get?

So when I get all this straightend out, Should it take care of my positive LTFT's? Right now, I have the IFR table scaled to achieve the negative LTFT's...

Chris, thanks for your help through all this...

ChrisB

Eric: There shouldn't be a limit, but I could have very easily screwed something up. If you email me your log file I will take a look at it and figure out what is wrong.

BillC5: You are "over-thinking" this. VE in a classical sense is actually not needed at all in a MAF vehicle. The MAF is going to tell you how much air the motor is moving, and you fuel for this. The o2's will tell you *exactly* what you are hitting (at least with respect to a stoich target) - so no motor changes, etc. will "fool" the o2's.

The blower will definitely increase the VE - even if you aren't in boost it may very well be kicking it up, as it is still a more effecient compressor than the engine is. You can't really do anything with data where the map is 105 or higher, but you could pull out all other data and calculate the VE based on those points and enter that. It should help it, though in the end it still falls down to trial and error.


Joe: Yep, you just have to try and hit as many cells as you can with driving. This may require hitting high rpm /low tps, high tps low rpm, etc - and other "wierd" situations you normally don't see. Plus there are just going to be cells you don't hit. (but since you never hit them they really don't matter effectively). I would try and get as many cells as you can, and then take a look at the slope coming up to the cells on the border - if it is going down, continue to "smooth by hand" in a downward trend, etc.

billc5

iTrader: (1)

Chris: Yes I agree I am over thinking. What I would like to do is get rid of the soot build up on the tail pipe which has appeared since the installation of the blower and Headers.

So I guess what you are suggesting is that the there is no way to calibrate the fuel to maintain 14.7 within the chamber. We have to live with 14.7 in the exhaust as measured by the narrow band O2 sensors and assume the obnoxious content is acceptable as there is no means to account for it.

Since the addition of my bolt-ons has increased the VE then by definition the AFR within the chamber has decreased (richer)and we must live with it within closed loop operation.

One thought was to raise the Stoich number to say 15.0 however the narrow band O2's are designed for 14.7 only. (I'll give it a rest now).

66ImpalaLT1

Chris, I was just going to email you my huge log file when I realized that since combined 4 logs I forgot to remove the header row from them. I'll try it again tonight and email you if I still have problems.

Eric

JxxxOxxxE

iTrader: (1)

Chris, any news on the VE only program?

Bink

^^^^^up
joel