Flat Shift

Flat Shift

Flat Shift

The Flat Shift 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.



Flat Shift

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.

Throttle Blip on Down Shift

Enable - Enables throttle blipping on downshifts. This will enable the Throttle Blip Amount and Throttle Blip Duration tables.

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. This table is used to ensure the clutch is fully disengaged before a throttle blip event begins.

Trigger 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 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.

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.


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.
  1. The exit conditions for this state depend on the Flat Shift Mode.
  2. Closed Loop exits this state when Gear Detection detects that it's in the new gear.
  3. While Active exits this state when the input and/or conditions are no longer met.
  4. Timed just checks that the time in this state exceeds the Torque Reduction Time.
  5. 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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