Thanks
to Ellis Groo for the A4 section, and John Lamb and Jeff Clarke for
help
with the VE section.
Please
send any corrections/additions (especially for fields marked with ???)
To Christopher_Bennight@Baylor.edu
Last
Update:
Version
1.9
Main
Display
Notepad:
This is a scratch pad area where information about a specific file
can be stored internal to that file.
Information stored here will not effect operating of the vehicle, but
comments will only be viewable with LT1 Edit.
Function Enable:
For all values, 1=enabled, 0=disabled.
Traction Control:
This will toggle traction control on or off. On cars without traction control it cannot be
enabled through the computer, since special hardware is also required.
Speed Density:
When this is enabled MAF input will be ignored, and fueling
calculations will be made with the MAP sensor alone. This mode is much harder to tune correctly
than MAF mode, and will not run as will unless the effort is invested. It is also less adaptable to changing weather
conditions. It does allow for the
removal of whatever restriction the MAF sensor imposes.
Crank Air:
When the vehicle is initially started the airpump is turned on to
provide air to the catalyst. If you have
catalytic converters this needs to be enabled, otherwise you can disable it.
Vehicle Anti Theft:
This toggles the VATS system (the system that reads the resistance
value from the pellet (resistor) in your key.
It can be toggled on or off. This
will not defeat the system completely on a y-body.
Transient Fuel:
This toggles the functionality of the Charcoal canister (Evap). If you have not removed this (not recommended
unless you know what you are doing) then this should be left enabled.
ENGINE
TEST
PARAMETERS TAB
EGR On:
The egr solenoid will be activated if the MAP sensor detects a
pressure greater than the value and if the RPM range falls within the listed
values.
EGR Off:
The egr solenoid will be de-activated if the MAP sensor detects a
pressure greater than the value listed and if the RPM range falls within the
listed values.
DTC32 test Parameters
Min MAP chng to Pass
The MAP sensor must detect a MAP change of this magnitude or
greater to enable a DTC 32 code.
Low VSS MPH
The VSS must be at a minimum this value to enable a DTC32 Test.
High VSS in MPH
The VSS must be at a maximum this value to enable a DTC32 test.
Low MAP to Enable
The MAP sensor must be at a minimum this value to enable a DTC32
test.
HARDWARE VERIFICATION
TAB
DTC Enable/Disable
DTC27
Can be toggled on or off. EGR
Solenoid.
DTC29
Can be toggled on or off.
Air pump related.
DTC32
Can be toggled on or off.
EGR solenoid test.
Idle Speed
This table contains the desired idle rpm setting which the
computer will attempt to maintain at idle.
It is scaled vs. Engine temperature in Degrees Fahrenheit. Typically idle is a bit higher at lower
temperatures to aid in warm-up. If you
change this value you may also have to change the Idle Air Control table to allow
for enough air at idle, as well as the Advance for Closed TPS table to ensure
proper timing for increased idle rpm.
Idle Air Control
This table contains the Park IAC stepper position vs. Coolant
temperature in Degrees F. This is the number of steps the IAC motor (located on
bottom side of throttle body) will default to.
The max value here is 160. This
value should not be set to more than the motor actually requires, as the
computer will then have trouble keeping the rpm’s down at idle speed. The easiest way to determine proper values is
first to see if the stock table works - if not, view the position the IAC motor
will open itself up to under a stabilized idle, and set the park position to
approximately 5-10 steps lower. This
value will be adjusted when the throttle stop screw on the throttle body is
opened or closed. Some people like to
target 30-40 at idle (no-ac). One should
note it has also been observed that setting the TB set screw so the IAC value
reads around 150 with AC on (~130 with AC off) has resulted in a better idle –
do to increased usage of dedicated IAC passages in the LT1/4 manifolds.
IAC Throttle Follower vs. MPH
This table contains the Throttle Follower IAC steps vs. RPM. This table will control the speed and
stability of the idle while in neutral but still moving. The value found in the table describes the
number of additional steps the IAC will open for a given RPM. This will typically cause the idle to be a
bit higher than the desired idle setting - which will ensure proper vacuum to
operate brakes and other accessories while moving.
Cylinder Balance
There are two options here:
Idle cylinder balance
Off idle cylinder
balance
They work apply to the appropriate situations –idle being when the
TPS = 0, off idle being any other time.
C revision programs typically had this set to 1 (not used), while the E
revision programs made use of it.
Basically this table describes the relative fueling each cylinder will
get. A factor of 1.00 would be the
fueling amount calculated by the rest of the computer – if this number is
decreased, fueling is decreased. If this
number is increased, so is fueling.
This table can be used to compensate for an imbalance in air
distribution.
FUEL
Open Loop Temp vs. Load
This table contains the Desired Air Fuel Ratio scaled vs. MAP
sensor reading(load) and engine temperature in degrees C. It should be noted that this table, as it’s
name implies, is only referenced in open loop operation. This does not include WOT by default (PE mode
is not the same thing as Open Loop – open loop here referring to the bit set in
the PCM). Typically this table is altered to achieve better
emissions/drivability at startup or if open loop mode has been enabled on the pcm. It should be noted that the value will not be actual
A/F ratio, but rather what the computer determines the A/F ratio *should* be
based on amount of air and fuel observed/added.
Closed Loop Enable Temp
These are the boundaries (maximal and minimal) between which
closed loop operation will be allowed.
If an open loop only program is desired both of these values are
typically set to 150. Values are in
degrees Centigrade (C).
Inj Offset vs. Volts
This is the injector offset versus voltage table. Fuel injectors are simply solenoids which
actuates some type of valve to allow fuel pressure to push out the fuel. As voltage changes the amount of time it
takes to open this valve will change.
Injector size, type, construction, and fuel pressure will also effect this value.
Higher fuel pressure will cause the opening time to be slightly longer
than at rated psi.
This value is the time in mS that the
injectors take to fully open their valve.
This value will be specific to each injector setup.
IAT Scale vs. Air Flow
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WOT Table This
is the percent TPS that will be required for the WOT bit to be set in the
computer when the engine temperature is less than 151 C. This can be altered so that the computer is
always in PE mode at idle rpm’s (thus O2’s are ignored) if so desired.
PE vs. Coolant Temp
This table contains the Power Enrichment (additional fuel) that
will be added at WOT vs. the coolant temperature when in PE mode (WOT)
PE vs. RPM
This table contains the Power Enrichment (additional fuel) that
will be added at WOT vs. the current RPM.
This is typically where fuel tuning for WOT operation is done. Values can be positive (Adding fuel) or
negative (Subtracting fuel).
Volumetric Efficiency:
It was determined by John Lamb that the value is defined by the
following relationship.
VE = Actual airflow(MAF)
-------------------------------
(RPM/120 * Air Density *
5.733)
Air density can be determined using:
(MAP – Vapor pressure(H2O))
---------------------------
0.287 * IAT(in Kelvin)
This is simply a re-arrangement of PV=nRT
(ideal gas law)
When the value in this table is
increased at a specific point fueling at that point will be increased, and vice
versa. This table is used typically in closed loop
mode to adjust the long term fuel trims so they are around 123-125.
MAF Calibrate:
This is a calibration curve for the stock MAF sensor. The stock sensor will output a frequency that
is proportional to the amount of air flowing through the sensor. This table tells the computer what each
frequency reading corresponds to with respect to flow rate (Gm/sec). The computer uses these data points to
construct a calibration curve to determine the flow rate for any reading within
the bounds of the table.
Injector Size
This is the expected flow rate for a single injector. The computer uses this to determine exactly
how much fuel is going in/how long the injector needs to be pulsed to add a
certain amount of fuel. Changes in injector size as well as fuel pressure will effect this value.
Cylinder Size
This is the expected number of cubic inches of each cylinder. This value times 8 should
give the displacement of the motor.
Many tuners do not alter this value even if the displacement has been
increased – choosing to rely on MAF increases as well as the PE vs. RPM table
for proper fueling.
IGNITION
Load vs. Advance:
There are two tables, one for 400-4000rpm, and the other for
4000-7000rpm. These tables contain the
commanded spark advance values for each set of RPM vs. Load values. If the rpm/load falls between data points the
computer will average to determine the correct value. WOT values will be typically in the 90-100KPA
range, depending on how much vacuum you pull at WOT. It should also be noted that there appears to
be a separate value that increases timing at WOT - values in the table still
change the total advance at WOT, but there is another value adding on to them.
Load Offset:
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Temp vs. Advance
Load vs. Coolant Temp
This table contains values vs. Load and Coolant temp that will
modify the values commanded in other tables.
When a value is read in this table for a given condition, that spark
modification will be applied to the total commanded value to increase or decrease
it.
Cranking advance
This is the amount of timing on cranking the motor.
Offset:
?????????????????????????????????????????????????
Closed Throttle Spark Advance
This is the amount of advance when the TPS reads zero. This will have a large effect on idle
quality, and may need to be changed with larger cams/increased idle rpm. A vacuum gauge can be used to help determine
the proper setting for this, as it will have a direct correlation.
Minimum Spark Advance:
The minimum spark advance that can be commanded for each set of
rpm values.
Offset:
???????????????????????????????????????????????????????????????????
Knock Retard
Attack vs. RPM:
This a factor that will effect how aggressive the computer is in
combating changes in the knock count value.
The greater the value the greater the amount of knock retard for a given
event.
Decay vs. RPM:
This is a factor that will effect how quickly knock retard is
degraded once the knock counter has stopped incrementing. The greater the magnitude of this value the
more quickly spark retard will return to zero on absence of any knock
detection.
Minimum Coolant Temp:
Minimum Coolant temp in C for knock
retard to be active.
Burst Knock
Enable Temp:
Minimum temp for burst knock to be enabled.
Lo Octane Retard:
This is the amount of timing that will be take
out across the board when low octane mode is entered.
Knock Count to enable:
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Max Retard:
Max Retard vs. RPM
This table contains the maximum amount of knock retard that can be
commanded at each rpm value.
Max Retard vs. MAP
This table contains the maximum amount of knock retard that can be
commanded at each MAP pressure.
Traction Control Retard:
This table contains the maximum amount of retard the traction
control module can call for at each rpm value.
M6 Tranny:
CAGS
Speed in MPH
These values are the speed in MPH at which the CAGS solenoid will
be enabled and disabled.
Load in KPA
These values are the MAP sensor readings at which cags will be enabled and disabled.
Enable Temperature
This is the temperature, in Deg. F at which the Cags system will become active. An easy way to disable this is to set the
value to 250 or some other high value you should never see.
RPM to disable
This is the RPM at which the cags
solenoid will disable.
%TPS to disable
This is the value at which the CAGS solenoid will be disabled.
A4 Tranny
(Thanks to Ellis Groo)
SHIFT SPEED TAB
Normal Mode
Shift Points vs. MPH
This table lets you control shift points while in the "Normal" switched position. This is when you first start the car and the mode 99% of the people drive in. This table has entries that let you insert figures that equal MPH. If you choose say 25% vs. 1-2 and insert 28MPH. This will not let the transmission till 28MPH when you are at 25% TPS. The first half of the tables are UP shift tables the second DOWN shift tables. Your down shift tables MUST be lower then your upshift tables for the same values or the car will not shift. These tables control how many gears the transmission drops for a certain MPH and TPS%
Performance Mode
Shift Points vs. MPH
This works the same as "Normal" mode except the PCM Is switched into the mode by a momentary switch and lights a LED to let you know you are there. Both Andrew and I have info on this and so far we have yet to have a car that CAN NOT be tripped into this mode. Mine is called the "12 second Mode"
Manual Mode
Shift points vs. MPH
This table is chosen when the shifter is not in the D or OD position. Most of the values are too high to achieve a shift. This is so WHEN you are in a manual position the trans will NOT shift until you shift it. The Downshift tables are setup kind of the same way so you stay in the gear you choose longer.
Kick Down Mode area
Normal Shift Rpm = unsure need more info. Stock is over 5k and HPP+ is 1k??
??????????????????????????????????
Hot Shift RPM
????????????????????????????????????????????????????????????????????????????
WOT Shift MPH
This table set upshift and down shift by MPH for WOT and override all other tables! This is where you would want to adjust your Upshift RPMs but have to convert to MPH. This also controls what MPH/RPM the transmission will down shift at under WOT. for dynoing a Auto I set my Up shifts and down shifts as follows.
1-2 = 10
2-3 = 15
3-4 = unchanged
2-1 = 5
3-2 = 10
4-3 = unchanged
This will get you in 3rd gear at 15 MPH and HOLD it there for the entire run
Hot Shift RPM
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Odd it matches the WOT tables but have no clue why
Low gear Upshift MPH
This is the maximum MPH which
will allow an upshift into first gear (Low).
SHIFT FIRMNESS TAB
Shift Pressure vs.
Temp
This table sets parameters for cold weather warm up and over heating conditions as well as normal operation pressures. When the trans is cold you have higher pressures to make up for cold parts that will leak fluid internally till warmed up. When the trans is to hot it also raises pressures to make up for thinner then normal fluid being lost in moving parts. Some bump these numbers but I prefer to do it in the Offset tables.
Line Pressure vs. TPS vs.
0-64MPH
This is half of you main pressure tables and the one your transmission uses the most. It references pressure from the base table set in Shift Pressure vs. Temp. The numbers entered are numbers that equal a CALCULATED PSI addition.
Line Pressure vs. TPS vs.
over 64MPH
This is half of you main pressure tables and the one your transmission uses the most. It references pressure from the base table set in Shift Pressure vs. Temp. The numbers entered are numbers that equal a CALCULATED PSI addition.
Normal/Performance Mode
Pressure offset vs. %TPS
These tables control Pressure offset in either Plus or minus numbers making shift harder or softer then the main table commands. I use these tables to do most of my pressure tuning. My "Normal" mode shifts like a Cadillac until around 30-40% or so then get harder for the extra power. My PERF. More is my full race mode. These are also the tables I used to adjust for my 58mm Throttle body.
Mamimum Line Pressure in PSI
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TCC TAB
TCC Apply vs. %TPS in MPH
This table is similar to the Up shift side of the tables only controlling the Lock Up Apply. This table also uses MPH for the base
TCC Release vs. %TPS in MPH
This Table controls the release of the Lock Up. The numbers in this table MUST be lower then the same numbers in that same table On the Apply tables or NO Lock Up will be achieved
TCC MPH Threshold
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TCC Shift Delay
??????????????????????????????????????????????????
CHECKSUM
This setting will show the calculated and read checksum for each
of the chips in the computer. This will automatically be done when saving a
file, so no concern needs to be given to this menu – other than to check if a
file you haven’t run Before (received from someone else) has a correct checksum.
GEAR/TIRE
This is where scaling for different gear/tire sizes is done. First the car type/transmission type is
selected, and then the tire size or diameter will be entered. Normally the Speedo and transmission setting
will be scaled the same, so both will be checked, and the new gear value should
be entered. Then press apply.
CHASSIS
Fan On Coolant Temp
First Stage Fan:
Under Speed:
This is the temperature at which the first fan will turn on when speed
is under the "Fan Speed Threshold" value.
Over Speed:
This is the temperature at which the first fan will turn on when
speed is over the "Fan Speed Threshold" value.
Second Stage Fan:
Under Speed:
This is the temperature at which the second fan will turn on when
speed is under the "Fan Speed Threshold" value.
Over Speed:
This is the temperature at which the second fan will turn on when
speed is over the "Fan Speed Threshold" value.
Fan On Oil Temp
First Stage Fan:
Under Speed:
This is the temperature at which the first fan will turn on when speed
is under the "Fan Speed Threshold" value.
Over Speed:
This is the temperature at which the first fan will turn on when
speed is over the "Fan Speed Threshold" value.
Second Stage Fan:
Under Speed:
This is the temperature at which the second fan will turn on when
speed is under the "Fan Speed Threshold" value.
Over Speed:
This is the temperature at which the second fan will turn on when
speed is over the "Fan Speed Threshold" value.
Hysteresis:
This is the temperature range that the coolant temperature must
cover for a fan to be turned off once it has been activated. For example, if
fan one turns on at 180, and cools down the motor, it will not be turned off
until the temperature is 175 if the hysteresis is set
to 5. It can be set individually for
each fan.
Fan Speed Threshold.
This is the speed value that effects the
fan under and over speed settings.
Limiters
CutOff
Speed:
This is the velocity at which fuel will be turned off at.
1st Gear:
This is the RPM at which fuel will be turned off at for first
gear.
2 to 6:
This is the RPM at which fuel will be turned off at for gears 2-6.
Resume:
Speed:
This is the velocity at which fuel will be resumed after a cutoff
has occurred.
1st Gear:
This is the RPM at which fuel will be resumed after a cutoff has
occurred.
2 to 6:
This is the RPM at which fuel will be resumed after a cutoff has
occurred.