Pages: [1]
Author Topic: How are the different load axises related?  (Read 10065 times)
Nottingham
Full Member
***

Karma: +13/-1
Offline Offline

Posts: 204


« on: June 27, 2012, 09:48:58 AM »

My stock KFMIRL map tops at around 180%, which means the maximum possible boost is around 1.1bar.
In order to raise the boost higher I have to increase the higher end of KFMIRL table.

While the original KFMIOP axis goes up to 160%, what happens if KFMIRL requests higher load than 160%?
I have already rescaled and recalculated both the KFMIOP axis and data to match the new KFMIRL.
Since KFZWOP(/2) share the x-axis with KFMIOP its values need to be scaled too.

However there are several other axises indicating load % (e.g in KFZW/2, KFKHFM, KFLF, KFLBTS, etc) with percentages varying from 150% to 185%. How are the different load axises connected and what happens if some maps are rescaled / calculated while the other maps are left alone?

Thanks Smiley
 
Logged
masterj
Hero Member
*****

Karma: +62/-5
Offline Offline

Posts: 1049



WWW
« Reply #1 on: June 27, 2012, 09:59:00 AM »

My stock KFMIRL map tops at around 180%, which means the maximum possible boost is around 1.1bar.
In order to raise the boost higher I have to increase the higher end of KFMIRL table.

While the original KFMIOP axis goes up to 160%, what happens if KFMIRL requests higher load than 160%?
I have already rescaled and recalculated both the KFMIOP axis and data to match the new KFMIRL.
Since KFZWOP(/2) share the x-axis with KFMIOP its values need to be scaled too.

However there are several other axises indicating load % (e.g in KFZW/2, KFKHFM, KFLF, KFLBTS, etc) with percentages varying from 150% to 185%. How are the different load axises connected and what happens if some maps are rescaled / calculated while the other maps are left alone?

Thanks Smiley
 

what happens is that KFMIOP 160% is limiting KFMIRL. You'll have to change axis of kfmiop and then rescale kfzwop/2 maps and few more maps since they're sharing same axes
Logged

Nottingham
Full Member
***

Karma: +13/-1
Offline Offline

Posts: 204


« Reply #2 on: June 28, 2012, 01:30:09 AM »

I´ve seen some "pro-tuned" files which have KFMIRL raised, yet the KFMIOP load axis left alone (as well as the other load indicating axises). The KFMIOP table values (axis from KFMIRL and ultimately from KFPED?) are recalculated correctly thou. The boost is also at the levels it should be.

Is it possible that the ECU extrapolates the new values when the upper limit of some load axis is exceeded, or simply use the last known value pointed by the highest available load percent in the specific map. E.G if KFMIRL requests 191% at 100% (PED), LDRXN has limited the load to 180%, and the KFZW load axis goes only up to 150%. Then the ignition angle would be set to value pointed by KFZW map @ 150% (Y) and the RPM (X)?

Since the KFMIOP should be limiting the load I recon the ECU indeed does extrapolate.

I checked some BAM/BFV maps and they have all of the load axises set higher than the maximum load allowed by LDRXN.
So maybe I´ll just borrow the axises from a higher end model files and recalculate the table values.


« Last Edit: June 28, 2012, 01:33:58 AM by Nottingham » Logged
prj
Hero Member
*****

Karma: +1072/-485
Offline Offline

Posts: 6041


« Reply #3 on: June 28, 2012, 03:42:11 AM »

Last value is always used, no extrapolation.
Logged

PM's will not be answered, so don't even try.
Log your car properly - WinOLS database - Tools/patches
masterj
Hero Member
*****

Karma: +62/-5
Offline Offline

Posts: 1049



WWW
« Reply #4 on: June 28, 2012, 03:49:50 AM »

I remember that my "pro" tuner did something like raising kfmirl and kfmiop and kfzwop... and also set lamfa > 1 Cheesy very funny tune it was... although it worked but I suspect that load model was miscalculating torque..
Logged

Nottingham
Full Member
***

Karma: +13/-1
Offline Offline

Posts: 204


« Reply #5 on: June 28, 2012, 07:31:06 AM »

Checked the relation with a proper damos, following maps share the same axis.

KFZW

Shares the Y-axis (called "sampling points for air charge SRL12ZUUW") with:

KFZW2
Ignition angle delta during continuous knocking (KFDZK)
Threshold of late ignition angle adjustments for ignition angle map switching (KFSWKFZK)
Most retarded (ATDC) ignition angle for continuous operation (KFZWMS)

----------------

KFMIOP

Shares the Y-axis (called "sampling points for air charge SRL11OPUW") with:

KFZWOP
KFZWOP2
Speed and weight correlation to drag (KFMDS)

----------------

KFLBTS

Shares the Y-axis (called "sampling points for mixture control SRL12GKUW") with:

KFFDLBTS

KFLF & KFKHFM have their own axises.



Logged
nyet
Administrator
Hero Member
*****

Karma: +608/-168
Offline Offline

Posts: 12271


WWW
« Reply #6 on: June 28, 2012, 10:46:20 AM »

Excellent summary. Thanks.

BTW i have spreadsheets of a few of the various map packs floating around that are ripe for datamining....

http://nyet.org/cars/files/

check out  the csvs...

they're missing axis locations, but I can add them easily.
« Last Edit: June 28, 2012, 10:47:54 AM by nyet » Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

Please do not ask me for tunes. I'm here to help people make their own.

Do not PM me technical questions! Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your ex
Nottingham
Full Member
***

Karma: +13/-1
Offline Offline

Posts: 204


« Reply #7 on: June 29, 2012, 09:40:50 AM »

Now I understand why even the professional tuners donĀ“t bother correcting the values...
There are simply too many maps to be scaled, it would take weeks just to get them all rescaled... even to stock values let alone tuning them.

It was already known that KFMIOP and KFMIRL are closely related.
KFMIOP has a little brother called KFMI_UM which is connected to KFMIRL the same way KFMIOP is (pointer map).
And KFMI_UM (Optimal engine torque map for monitoring function) happens to share its axis (indicating air charge, RLV08_UM) with KFZW_UM (Optimal ignition angle map for monitoring function), atleast.

I have not digged deep enough yet, but I recon there are 100+ maps to be rescaled just to get everything align with the altered KFMIOP (stock calibration style). I recon it would be easier to modify a SW for 210/225/240bhp variant to work properly on lower end variant.
Logged
nyet
Administrator
Hero Member
*****

Karma: +608/-168
Offline Offline

Posts: 12271


WWW
« Reply #8 on: June 29, 2012, 09:56:00 AM »

Yup. This is why starting with the k-box is probably a good idea...

The two biggest limitations are load (which is solved in the kbox) and MAP (which can't be solved w/o rewriting the code, or underscaling a larger MAP)
Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

Please do not ask me for tunes. I'm here to help people make their own.

Do not PM me technical questions! Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your ex
Nottingham
Full Member
***

Karma: +13/-1
Offline Offline

Posts: 204


« Reply #9 on: July 01, 2012, 06:21:39 AM »

Ok, went thru couple thousand of maps but now I am done...

You can probably get a way if you leave some of these alone, but the ignition angle related maps definitely need to be recalculated if you alter the air charge calibrations or even raise the boost past the default values Roll Eyes
This is because more pressure = higher flame speed = ignition angle needs to be retarted (less advance).

To keep the ECU load / air charge calculations sane (stock calibration way) following maps need to be recalculated:

Recalculate the values and rescale the air charge indicating axis to match the altered KFMIOP (X-axis) maximum value:

KFBALB
KFDZK
KFFDLBTS
KFFWTBR
KFKHFM
KFLBTS
KFMDS
KFMI_UM
KFSWKFZK
KFZW
KFZW_UM
KFZW2
KFZWMN
KFZWMNST
KFZWMS
KFZWOP
KFZWOP2


Recalculate the values and scale the air charge indicating axis to match LDRXN maximum value (±5%):

KFPBRK
KFPBRKNW
KFTATM


Check the sanity agains KFMIRL vs. KFMIOP map (lookup style):

KFMI_UC
KFZW_UC


Just remember, once you do this... Make sure you set the new KFMIOP maximum air charge high enough so you don´t ever have to do this process again  Grin
« Last Edit: July 01, 2012, 06:27:06 AM by Nottingham » Logged
Pages: [1]
  Print  
 
Jump to:  

Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Page created in 0.019 seconds with 16 queries. (Pretty URLs adds 0.001s, 0q)