Clutch-by-wire or virtual clutch as some may call it can be used with many transmissions running HTG tuning Gearbox Control Unit. We support CbW functionality with any dual clutch transmission and also with various hydraulic ones like 8hp70, 6hp series.
Take-up (starting of drive) remains unaffected – GCU will perform clutch control, use of clutch pedal is optional. Clutch by wire is a must-have function for drifting. 🙂
How to connect clutch input to GCU #
CbW functionality can be triggered with any kind of input – analog, digital, CAN message.
Assigning analog signal or proportional CAN message gives You ability to control clutch proportionally. Using digital (0-1) inputs like switches will result in instant transitions. Choose Your triggering method based on application needs.
Switches or potentiometers – feed them with GCU 5v_out (M1) and connect signal into available analog / digital input.
CAN based inputs – add them to CAN bus and define in CAN configuration using HTG Config software
How to configure Clutch-by-wire #
Check GCU Linearization if haven’t yet.
Input should report 0% (0) when CbW pedal is in idle position (not pressed) and 100% when fully pressed (1024).
Clutch engagement input is final percentage clutch pressure reduction. While CbW level is 100% (1024) final clutch pressure as result of tables is is reduced by 100%- full clutch disengagement. This is the value that CbW pedal should report when FULLY pressed.
While CbW level is 0% (0) clutch pressure will remain unchanged. This value CbW reports while NOT pressed.
On CbW min/max positions are calibrated in IO config, enable interpolation has to be checked afterwards.
Clutch By Wire linearisation #
It is possible to apply Clutch-by-Wire linearisation with HTG tuning Gearbox Control Unit.
That table adjusts feel of CbW pedal response (proportional sensor).
If the input is a digital input (switch for example) that table has no use, it can be used to limit maximal points of the switch.
To enable clutch-by-wire linearisation select create “MAP input” object.
Map input can be created under (Shift + Q) IO Definition panel.Create new MAP input object and name it in preferred way, like CbW_linearisation. Then assign input that You would like to map, so in this case it has to be already calibrated CbW input. Double clicking Mapped Value brings up new window where actual mapping is done.
X axis of clutch linearisation table is CbW pedal travel (linearized) while Y (ouput) is % reduction of pressure.
Above example should be interpreted with such form: pressing CbW pedal from 0% (idle) to 20% will reduce clutch pressure by 5% with a little bit of exponential, 40% will reduce 15% of pressure and so on.
IMPORTANT: CBW above 50% (after mapping) triggers take-up override, so make sure that while drifting your preferred kick travel exceeds mapped 50% value.
Please keep in mind that properly tuned clutch pressure is just little bit above required clamping pressure, so small % of reduction is sufficient to cause slip and disengage drivetrain. It’s important to make sure that fully pressed pedal fully disengages drivetrain to avoid overheating clutches while pedal is fully pressed.