Flat Shift / Throttle Blip
The Flat Shift / Throttle Blip function allows for full throttle gear changes to occur without throttle lifting. There are a number of types of Flat Shift but this is commonly used for sequential gearboxes with an input from a load cell. The engine power is then cut for an amount of time to allow the gear change to take place. Too short a time and gears can clash, too long a cut time and the shift will be slow and abrupt to the drive.
Also allows for throttle blips on downshifts for both clutchless downshifting sequential transmissions and rev-matching H-pattern transmissions.
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Wiring Tab
Options
Conditional Trigger
Allows certain ECU conditions to be configured to activate the Flat Shift function.
Flat Shift Input Enable
Allows configuration of an input to the Elite ECU that triggers the Flat Shift function. The type of input is configured in the Input Select settings.
Input Select
The type of input to be used.
Flat Shift Switch
Select when a direct input to the ECU is used to activate the Flat Shift function, such as a dedicated aftermarket load cell.
Clutch Switch
Select when activation of the clutch switch will trigger the Flat Shift function.
Load Cell
Select Load Cell when a load cell is used to determine Gear Selector Position. This will open a new tab in the Flat Shift function whereby the voltage calibrations for the upshift and downshift positions can be determined.
Connections
Flat Shift Switch Input
Available when the Flat Shift Switch is enabled and the Input Type is set to Flat Shift Switch. Select an appropriate input to be used for this function. An AVI or SPI may be used.
SPI
An SPI (Synchronised Pulsed Input) requires configuring of the edge and the type of Sensor to be connected.
Edge Select
Falling is used when the input is grounded when the switch is activated. Rising is used when the input is supplied voltage when the switch is activated.
Sensor Type
Set to Hall Effect for all switch inputs
Pullup
Enables a pullup if required to generate a voltage when the switch is off.
AVI
An AVI will require Switch On and Switch Off voltages to be configured so the Elite ECU can know which voltages on the AVI meet the conditions required.
Switch On Voltage
The voltage either above or below where the switch is considered to be ON. When selecting an appropriate value some consideration should be given to allow for voltage fluctuations.
Switch Off Voltage
The voltage either above or below where the switch is considered to be OFF. When selecting an appropriate value some consideration should be given to allow for voltage fluctuations. Eg. if the switch is at 5V when it is Off and is grounded to 0V when the switch is On, you would set the On voltage to 1.0V and the Off Voltage to 4.0V.
Example 1
The switch is at 5V when it is Off and is grounded to 0V when the switch is On. Correct settings with tolerance would be to set the On voltage to 0.5V and the Off Voltage to 4.5V. i.e. when the voltage falls below 0.5V it is considered to be ON, and when it rises back above 4.5V it is considered to be OFF.
Example 2
The switch is at 2.5V when it is OFF, and is at 12V when it is ON. Correct settings with tolerance would be to set the On Voltage to 4.5V and the Off Voltage to 3.0V. i.e. when the voltage rises above 4.5V it is considered to be ON, and when it falls back below 3.0V it is considered to be OFF.
Settings Tab
General
Mode
Select which mode of operation is to be used.
Closed Loop (If available to the ECU)
Closed Loop mode requires a Gear Position Sensor to be enabled in the Gear Detection function. Closed Loop Mode applies a full Torque Reduction until the shift is considered complete. Completion of the shift is determined by Gear Detection detecting that the new gear has been reached, then allowing a (short) extra amount of time to allow the gearbox to stabilise in the new gear before disabling the reduction. This small extra amount of time is given in the Flat Shift Time table.
While Active
The torque reduction will be active while the input conditions are met.
Timed
A full torque reduction will be applied for a configured amount of time. This reduction is applied for a time specified in the Flat Shift Time table.
Max Shift Time
If the ECU has not determined that a shift has ended within this amount of time, the recovery method will be automatically applied, and torque restored. This is prevent continual torque reductions while in gear due to input anomalies.
Blockout
The amount of time after a flat shift cut has occurred before another Flat Shift torque reduction can be initiated. This is to prevent repeated cuts due to input anomalies.
Torque Reduction
Torque Reduction Method
Select the type of power limiting to be used for the Flat Shift function.
Ignition Retard
Ignition timing is to be used to limit engine power. Selecting this opens a tuning table.
Fuel Cut
Injector outputs will be cut to limit engine power. Selecting this activates a cut percentage tuning table.
Ignition Cut
Ignition Outputs will be cut to limit engine power. This is the more common method. Selecting this activates a cut percentage tuning table.
Fuel & Ignition Cut
Both injector and ignition outputs will be cut to limit engine power. Selecting this activates a cut percentage tuning table.
Fuel Cut & Ignition Retard
Injector outputs will be cut and an ignition timing correction applied to limit engine power. Selecting this activates a cut percentage tuning table and an ignition correction table.
Ignition Cut & Ignition Retard
Ignition outputs will be cut and an ignition timing correction applied to limit engine power. Selecting this activates a cut percentage tuning table and an ignition correction table.
Fuel Cut, Ignition Cut & Ignition Retard
Both injector and ignition outputs will be cut to limit engine power, along with an ignition timing correction. Selecting this activates a cut percentage tuning table and an ignition correction table.
Recovery Method
Select the method used to reintroduce torque after a shift and torque reduction have taken place
Instantaneous Recovery
All applied torque reduction methods (cuts and/or retards) will be instantaneously restored after a shift has taken place.
Ramp Out Retard Only
The ignition timing will be slowly restored over a period of time once a shift has completed. If any fuel and/or ignition cuts are used for torque reduction, the injector and/or ignition outputs will be restored instantaneously upon completion of a shift event. Selecting this activates a Recovery Time tuning table.
Ramp Out Cut Only
The applied fuel and/or ignition cuts during a torque reduction will slowly be restored back to normal operation over a period of time once a shift has completed. If any ignition retards have been applied, the ignition timing will restore instantaneously upon completion of a shift event. Selecting this activates a Recovery Time tuning table.
Ramp Out Cut and Retard Together
All applied torque reduction methods (cuts and/or retards) will slowly be restored over a period of time upon the completion of a shift event. Selecting this activates a Recovery Time tuning table.
Shift Direction
Select the shift direction that flat shift torque reductions should occur.
Up Shifts
Flat shift torque reductions will only occur on up shifts.
Down Shifts
Flat shift torque reductions will only occur on down shifts.
Up / Down Shifts
Flat shift torque reductions will occur on both up shifts and down shifts.
Min TPS
The Throttle Position must be greater than this amount before a Flat Shift cut can occur.
Min RPM
The Engine RPM must be greater than this amount before a Flat Shift cut can occur.
Throttle Blip on Down Shift
Enable
Enables throttle blipping on downshifts. This will enable the Throttle Blip Amount and Throttle Blip Duration tables in the ECU navigator.
Rev Match Limiter
This enables a soft ignition cut to be applied if the throttle blip causes the RPM to climb above the Throttle Blip RPM Target (the correct rev-match for entering the next gear).
Min Speed
The vehicle speed must be greater than this amount before throttle blip will be enabled.
Min RPM
The Engine RPM must be greater than this amount before throttle blip will be enabled.
Delay
The throttle blip will delayed by this amount. This can be used in cases such as if a clutch switch changes state before the clutch is completely disengaged.
TPS Correction
The rate of throttle reduction per second once target RPM is reached.
Gear Tolerance Enable
Activates the Throttle Blip Gear Tolerance table in the ECU Navigator. This table i s used to ensure the clutch is fully disengaged before a throttle blip event begins.
Conditional Trigger Tab
When Flat Shift Switch is On
And/Or
Allows conditions to be combined so that multiple conditions must be met to enable the Flat Shift.
Select
Select the ECU channel to be used.
Maths
A selection of Equal To, Not Equal To, Greater Than, Less Than, Greater Than Or Equal To, Less Than Or Equal To that is to be used.
Value
The value the maths must meet to enable the condition.
Load Cell Tab
Only available when the Flat Shift Input is set to Load Cell
Up Shift
Voltage
This is the voltage read by the ECU from the Load Cell when the shifter is in the Upshift position. To calibrate this voltage, reset the ECU, reopen the Flat Shift Function, push the shifter into the upshift position and click the calibrate button. The calibration should be displayed automatically.
Hysteresis
The Load Cell voltage must drop below or exceed the upshift Calibration by this much before the shifter is considered to have returned to the rest position or be out of range. This is to account for signal noise and slight shifter movement. Suggested values for the Hysteresis is half of the distance between an Upshift calibration and the rest position voltage.
Down Shift
Voltage
This is the voltage read by the ECU from the Load Cell when the shifter is in the Downshift position. To calibrate this voltage, reset the ECU, reopen the Flat Shift Function, push the shifter into the downshift position and click the calibrate button. The calibration should be displayed automatically.
Hysteresis
The Load Cell voltage must drop below or exceed the downshift Calibration by this much before the shifter is considered to have returned to the rest position or be out of range. This is to account for signal noise and slight shifter movement. Suggested values for the Hysteresis is half of the distance between an Downshift calibration and the rest position voltage.
Related Tables
Flat Shift
Ignition Retard
Available when the Flat Shift Cut Type is set to Ignition Retard. This allows for up to 3D (8x8) mapping of ignition retard to be used to limit engine power during flat shift.
Percentage Cut
Available when the Flat Shift Mode includes fuel and/or ignition cuts. This allows for up to 3D(8x8) mapping of the percentage cut to be applied during a flat shift in order to reduce torque.
Recovery Time
Available when the Recovery Method involves a Ramp Out. This is the amount of time that the cuts and/or ignition corrections will take to recover completely after a flat shift event. Typically in the 10 to 100ms range. Up to 3D tuning is available.
Throttle Blip
Throttle Blip Amount
The commanded throttle position percentage. During a blip event, the throttle will open to this throttle position unless a conditional setting forces an exit.
Throttle Blip Duration
The amount of time (in ms) for the blip to occur. A cell value of 1000 will incur a blip of set percentage to occur for 1000ms, or until a conditional setting forces an exit.
Throttle Blip Gear Tolerance
This setting is used by the Throttle Blip Gear channel to determine whether a vehicle is in gear or not at any point in time. This is a rotational speed tolerance between the engine rpm and wheel/driveline speed, and is used to ensure the clutch is fully disengaged before a throttle blip event begins.
E.g If Gear Ratio 2 is 21 km/h per 1000 RPM and the Gear Tolerance is set to 5%, throttle blip gear would report 2nd gear if the current gear ratio was within +- 5% of 21km/h per 1000 RPM. In other words, if the gear ratio was above 19.95 km/h per 1000 RPM or below 22.05 km/h per 1000 RPM then it would be be in the tolerance range of the gear 2nd gear.
Related Channels
Flat Shift States
For Datalogging and Table purposes, Flat Shift States are:
0: Requirements Not Met. Flat Shift has a min RPM and min TPS. No Torque Reduction used
1: Input Held On. This is to prevent a flat shift occurring immediately when the requirements are met if the switch is on and/or the conditional trigger is active. No Torque Reduction used.
2: Idle. Ready to perform a Flat Shift. No Torque Reduction used.
3: Pulling Out Of Old Gear. Gear Detection indicates that the old gear is still engaged. Full Torque Reduction table values are used. Only used by Closed Loop. Other modes skip it.
4: Shifting. Mid-shift. Full Torque Reduction table values are used.
The exit conditions for this state depend on the Flat Shift Mode.
Closed Loop exits this state when Gear Detection detects that it's in the new gear.
While Active exits this state when the input and/or conditions are no longer met.
Timed just checks that the time in this state exceeds the Torque Reduction Time.
Alternately: if the shift time exceeds the Max Shift Time setting.
5: Entering New Gear. Gear Detection indicates that the new gear is now engaged. Torque Reduction will continue for the Torque Reduction Time to allow the new gear to fully engage before entering Recovery state. Full Torque Reduction table values are used. Only used by Closed Loop. Other modes skip it.
6: Recovery. During this phase the Torque Reduction amounts are either immediately stopped or gradually faded out - depending on the Recovery method setting.
7: Post-shift Block-out. Prevents a new shift for the time specified in the Blockout Time setting. No Torque Reduction used.
Flat Shift Direction
For Datalogging and Table purposes:
-1: Down Shift
0: No shift
1: Up shift
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