Freak

Hey guys, trying to work out a KR problem, and have read about a guy on the LS1 edit mailing list, who says he is getting his just after lifting off the throttle. Im wondering if thats whats happening to me.

I always get it at high Kpa values (90-95 the last time i ataped it). that would be lots of vacum, like 27 in of hg or something, which seems like that would be throttle closed.

does that sound right?

thanks
Troy

Team ZR-1

KPA is the inverse of vaccum so at WOT high KPA, low vaccum

Example when my engine is at 95 KPA the vac is like 2.2

Freak

crap, thought maybe I was making some headway. oh well, back to the drawing board

thanks for the info

Bink

kPa, a unit of measure ,can be either absolute pressure or vacuum referenced . Our MAP sensors are absolute pressure. Atmosheric pressure (standard) is 101.3kPa.
So - 0kPa is a complete (Absolute) vacuuum and 105kPa is a little above atmospheric pressure. Most cammed cars seem to idle at about 40-50 kPa (MAP) .Then as the throttle is opened the kPa increases to max of 101.3 kPa( or a little above).

Vacuum referenced pressure kPa (inches of Vac) is referenced to atmospheric air/pressure. Atmospheric pressure is the Baseline of "0" and then amount of vacuum is actually the negative pressure below atmospheric. Our Injector flow rate table is Vacuum referenced. So WOT is 0 kPA and idle is 60-80 kPa.Vacuum referenced.

20- 40 kPa idle VACUUM is the same as 80 - 60 kPa ABSOLUTE (MAP) Referenced.


101.3 - absolute kPa = VACUUM kPa


101.3 - Vacuum kPa = ABSOLUTE kPa.

VE Table -Absolute referenced
IFR Table Vacuum referenced
Injector Offset- Vacuum referenced
MAP-Absolute referenced
Hope this helps some. All of this can basically be found in an old post by NoGo. He is the MAN!
joel(Bink)

Team ZR-1

Your clouding the issue, if you use a PCM scanner
( as was part of the question, he was using values scanner reported as to MAP since it was KPA he was mentioning and not inches of vaccum )
the higher the engine load is the higher the MAP reading is as to KPA.

As to LS1edit, that is not totally true, older versions had tables backwards but newer versons have reversed the scale values.

The tables as in version 1.21 of LSe1edit for injector flow were scaled from left 0 to 80 KPA, yet in scanning engine vaccum as per a scanner the low engine loads run about 20-25 inches and when at WOT about -5, thus the table never fit the window, so it was the table that was wrong and now is corrected in version 1.29 BETA as using MAP KPA.

Freak

thanks for the info guys

Team ZR-1, in regards to this part of your post...

does that mean that when I changed my IFR its going to be screwy? I am still on like 1.11 or something. maybe I should upgrade... are there any other tables like that?

Team ZR-1

Yes sure will.
( 1.11, that is a year old, 1.21 came out like last Nov)

Ever notice when you look at graph mode of injector flow table using stock table that at zero it is richer then at 80 ?

The line is lower left, higher on right side,
if that was really 80 KPA (PE) you would go richer not leaner.
Since vaccum as per scanner is in inches an engine would never get close to 80.

Now reverse the table where 80 KPA starts where zero was and now the graph line is correct.

Problem is as with your version the table started at zero to 80 but now carputing made the table start at 100 KPA on left and 20 KPA at right end.

Do a test, average out lets say trim cell 1, avg about 35 KPA, now in flow table at 35, reduce value by lets say 5% richer (95 multipler).

Flash, do your PCM learn time and then PCM scanner record and anlayze trim cells.
Did cell 1 go richer or did a cell at other end of table go richer.

Other changes Carputing has published on their e-mail listserver :

Version 1.29 Adds:

1) Maximum Brake Torque Timing - this table defines the maximum allowed
timing

2) Knock Allowed Time Table -97-98 only - This table defines how long
Knock is allowed before starting retard.

3) Knock noise Level - 98 only - should allow you to adjust the knock
sensitivity, Not tested yet.

4) Correction to IAT vs MAP location for 2001 and 2002 only

5) changes to Table Edit - There is now a menu bar on this form. You can
cut and paste a block of the table. It is useful for copying the High
Octane table to the Low Octane table. You can do the cut and paste from
one file to another. But you cannot exit the editor between files. This
can be used to cut and paste a table between two different GM Builds. It
is up to you to make sure the axis match.

6) Added A/C section to System Page, use these to set a %TPS or
RPM were the A/C is disabled, then a re-enable for the %TPS or RPM to
re-enable after disable.

7) Coolant Temp based spark Advance - Note the axis swapped from
2000 to 2001

8) Added the IAC park Position for 97-98 PCM's

9) Added the Cranking VE table for 97-98 PCM's

10) Change to the IAT timing for 2001 and Up. I just realized that GM
changed the Load axis from MAP to Gms/Cyl in 2001. This update corrects
the axis.

11) Added Tip-In Max. Knock Retard for 2003 Trucks

12) Add Delta Airflow to enable Burst Knock for 2003 Trucks

13) Added LTFT cell boundaries

14) Added LTFT Min and Max. Temperature thresholds to enable learning

15) Added new MPH limiter for 2001 and later to the Speedometer page

16) Changed the Axis values on the Injector Flow and Offset Tables, It
now shows #'s in KPA, not Vacuum.

17) added automatic scaling for Performance mode shift speed, and the
TCC speeds to the Gear scaling for Trucks and F bodies.

18) Added Speedometer Pulses per Mile, To allow calibration for non GM
Speedometers

19) Fix to correctly identify the 2003 Holden Series 2

20) Modified Burst Knock Degrees for 03 Truck

21) Limits Maximum Torque input to 639 Lb. Ft., This is an internal
limit in the PCM, that the User interface was ignoring.

22) Special Support for late 2000 Holdens

23) Map Parameters to tune P0121

24) PE enable RPM - Used in trucks PE delay is disabled above this RPM

25) changes to tire size scaling for 99-03 US Camaro and Firebird

26) Changes absolute tire size on all -- 99- 03 Vehicles except Corvette

27) New Throttle Cracker Frame. These parameters are used in 2001 and
later PCM's to hold the Idle at a fast idle When the car is moving, and
you let off the gas.

28) New LS1prog, with added support for 2003 Trucks

29) Adds support for a New 2000 GM Build - Segment 1 = 12584929

30) New table for DTC1514, This table is the allowed error for the
estimated airflow.

31) Maximum Grams/Cyl Airflow for ETC motors.

32) New Torque limiter in Torque Limiter Frame - Max. Engine Torque. Only
used 01-03, and not in 2002 Flex fuel 5.3L and 2003 trucks

33) New PArameter On Speed Limiters Page - Max. MPH/Second Change -
Actual scale is wrong, But raising value raises the Max. Delta airflow.

34) Fix Scale on Temperature axis of Engine > Limiters > Air flow table

35) Truncated display of Stoich ratio, and Max. enrichment and a few others.

36) Added Tire size calculator to car and truck tire calculations

37) Allows you to toggle the Platform Parameter. Good for tricks like
Setting a Vette engine up with a mechanical throttle.

38) Adds support for a New 1999 GM Build - Segment 1 = 12584929 THis 99
Build uses the System and Speed segments from the 2000.

Freak

holy crap, I hope you cut and pasted that.

yea I got edit when it first came out, but didnt do much with it but play wiht the idle a bit, and change things liek gears tires etc. till recently.I guess I should upgrade. when is the 1.29 version due out?

Team ZR-1

I do not know when they are releasing 1.29 to general public.

Would be easier for you to record Vaccum in KPA rather then MAP and then your inj flow table would be OK for then 0 would be PE and high KPA is lower trim cells.

ChrisB

The old table wasn't backwards, it was just scaled in Manifold Vacuum expressed in units of kPa. This *was* confusing though as nowhere was this indicated to be the case.

If the table now goes from 20-100kPa it sounds like Ken just did some math for you (assuming 100kPa is atmospheric).

I would have a concern about that though - it sounds like the table is internall scaled vs. vacuum (why ken initially set it up that way) - which would actually be Barometric (car measures at key on) - MAP.

Now if your barometric pressure is 100kPa (approx sea level) there is no problem. But what if you live up in denver and have a barometric pressure of 80kPa or so. At WOT you will read 80kPa, and determining your IFR cell this way would give you Baro - 80kPa, or 80-80kPa -- or the current 0 vacuum cell.

In the new table you would get an absolute reading of 80 kPa, which would correspond to 20kPa in the old table.

I haven't seen the new version, but I don't see how this could be addressed in runtime - so it sounds like it could have the potnetial to throw you off if your barometric pressure isn't 100kPa?

Team ZR-1

I was backwards via the confusion of end user seeing KPA and assuning the table was in MAP and thus newer version the table flips to where table starts at 100 KPA and ends on the right side at 20 KPA which does not make sense.

Most people set their PCM scanner to english values rather then metric thus MAP is KPA and vaccum is in inches, not KPA thus they were using the MAP values as being for tables such as inj flow.

NoGo

iTrader: (2)

I have the same concern. If the table is originally scaled as vacuum referenced in the PCM, then I think it should be left that way.


Team ZR1: The IFR table and Offset Table is not labled wrong, they are vacuum referenced.

Team ZR-1

Is is CONFUSING and why carputing changed it in 1.29.

Most people use english values, thus vaccum is in inches so now to capture in KPA they have to set to metric just for that value and then switch to english values captures to get the other values they want to see in that scale.
Also many people had problems tuning per trim cell and newer table format makes that easier to tune cells.

A lot of content in LS1edit document not very clear or missing info so many assumed KPA was MAP not vaccum.
Fuel trims are left to right, not right to left as old table had so table was in a backward state for some people and were tuning low cells from the left of table so again it was confusing for many.