Reduces power during gear shift.
Note: Advanced features in combination with sequential gearbox control is also available.
Switch activation can be triggered by either a physical digital input or using the Internal output system.
Shiftcut
Enable shiftcut
How to activate shiftcut function.
•enabled - Shiftcut functionality is always enabled.
•enabled by digital input - Activation of the function requires the digital input function Shiftcut enable to be activated.
Shiftcut mode
Specifies the shiftcut control method
•Timed pulse (shiftcut input) - When the digital input function shiftcut input is triggered, shiftcut function is activated during the cut time period.
•Timed pulse with table (shuftcut input) - When the digital input function shiftcut input is triggered, shiftcut function is activated with a table, and also extra options to control the ramp back time, see shiftcut ignition retard options below.
•Timed pulse from sequential gearbox control - Uses the shiftcut time table, where shiftcut can be stopped if a analog gear position sensor is fitted, see analog gear sensor feedback below.
•Input controlled (shiftcut input) - When the digital input function shiftcut input is triggered, shiftcut function is activated as long as the shiftcut input is active.
•Input controlled (clutch switch input) - When the digital input function clutch switch input is triggered, shiftcut function is activated as long as the clutch switch input is active.
•shift force controlled (strain gauge) - Uses the AIN (0-5V) shift force sensor class to activate the shiftcut function.
•Gear position sensor controlled - A shift cut is triggered when the gear position goes outside the min/max range set for each gear on the gear sensor setup page. Use the "Analog gear sensor feedback" to abort the shift cut as soon as the next gear is engaged.
It is really important that the VSS GEAR RealTime Data value goes to unknown between each gear when shiftcut mode = Gear position sensor controlled.
Cut time
Specifies the time (in seconds) engine power is reduced (shiftcut).
Cut output
Specifies engine cut method to reduce power
•Cut ignition - Only cut ignition.
•Cut fuel - Only cut fuel.
•Cut fuel and ignition - Uses both fuel and ignition cut.
•Drop % with tables - Drop either fuel or ignition, or both with tables.
analog gear sensor feedback
Used to stop an ongoing shiftcut when an analog gear position sensor sends a valid "new gear" signal. Used to minimize the shiftcut time.
Gear Counter Feedback
Ends the shift cut as soon as the gear counter increases/decreases. Can be used with sequential and H-pattern transmissions.
Set the time table to the max time and let the gear counter feedback end the cut as soon as the shift is completed. Uses VSS GEAR as the gear source.
Shiftcut conditions
Enable cut above TPS
Enable shiftcut activation only above this TPS value.
Enable cut above RPM
Enable shiftcut activation only above this RPM.
activation delay time
Specifies the time in seconds to delay the shiftcut function when the digital input shiftcut is triggered.
reactivation time
Specifies the reactivation time before any new shiftcut signal will be taken into account.
Note: any shiftcut signal will be discarded within the reactivation time.
max cut time
Specifies the maximum cut time (in seconds).
Shiftcut time (table)
Cut time
Specifies the time (in seconds) engine power is reduced (shiftcut).
Shiftcut ignition retard (and ramp back during time)
Retard angle
Extra options to retard timing during shiftcut.
hold time
A time table (in seconds) to hold the above retard angle ignition timing.
ramp back time
When the above hold time is reached, this table is used to ramp back the ignition advance to table values during the specified time.
Note: The retard and ramp back functions is used to smoothly increase power under a short period of time to let gearbox to "settle" and reduce torque.
Examples
Shiftcut mode: Timed pulse (shiftcut input).
When Shiftcut input is triggered, in this example MaxxECU cuts ignition for 250ms if all conditions is valid for activation (over 5% TPS, over 1500RPM). Max cut time, fail-safe max cut time.
Shiftcut mode: Timed pulse with table (Shiftcut input) / Timed pulse from sequential gearbox control.
When Shiftcut input is triggered, in this example MaxxECU cuts injection using the shiftcut time table when shiftcut conditions are met.
Note: You can always change axis sources, for example to use an external potentiometer, button or switch to alter shiftcut times.
Shiftcut mode: Input controlled (Shiftcut input/Clutch switch input).
When Shiftcut input / clutch switch input is triggered, in this example MaxxECU cuts fuel injection during the period the input is triggered, but for maximum 3 seconds when Shiftcut conditions are met.
See also, sequential gearbox control.
