GCU - Gearbox Control Unit

Clutchless shifts - Spark Cut & DBW Blip - USB programmable

System Description
Our GCU is an essential addition to any sequential transmission setup.  An accurate torque reduction during up-shifts at WOT and throttle blip on down-shifts under braking is required to obtain the most efficient operation out of your sequential transmission.

Dog-ring engagement is dependant on a torque reduction (synchronized with the shift level) to perform a smooth accurate shift. Torque reduction is performed by cutting power by a specified % (and duration, 0 to 500ms) to the ignition coils during a shift event. The shift event is initated by a load cell shift knob (Push or Pull) or steering wheel paddle switches. 

This allows for clutchless WOT (no-lift) shifting on upshifts, as well as clutchless (rev-matched) downshifts.

Our software provides the race engineer the ability to cut the ignition coil power by a given duration and/or percent based on the gear that the transmission is shifting into.  (When the transmission is equipped with a gear position sensor.)

Also See: DBW Standalone Throttle Blip Modules for H-pattern cars

Sensor Inputs:

  • Load Cell Shift Knob (Push-Pull) or (H-pattern)
  • Gear Position Sensor (optional)
  • Steering wheel switches from Paddleshift system (optional)

Calibration parameters:

  • Downshift Load Cell Threshold (mV)
  • Upshift Load Cell Threshold (mV)
  • Ignition Cut %
  • Throttle Blip Target % (for downshifts)
  • Table: Calibrate Gear Position Sensor (Gear pos vs volts)
  • Table: Shift duration by gear (ms)
  • Table: Upshift duraiton (ms) vs Gear
  • Table: Downshift duraiton (ms) vs Gear
  • Delay after Thres. (ms)
  • Minimum Time between shifts (ms) - Buffer to prevent double cut

Sealed Enclosure and Harnesses

Cinch Enclosure and Molex MX150 Connectors
Dimensions: 5.2" x 2.8" x 1.7"

USB Programmable

Windows PC program.

Video - GCU in Action

VIR 1:55's in a Katech 427 LT1 C7 Corvette

Katech Track Attack LT1 motor, PPG sequential transmission, Xineering GCU, DSC Sport shocks and controller, AP Racing Radi-Cal brakes, AMT Motorsports spherical bushings.

Hendrick Motorsports Track Attack - Carolina Motorsports Park - 1:32.78

Chevrolet Performance LSX454 engine, RTS 6XD sequential transmission w/ Xineering GCU for clutchless shifting.

Feras Q - SuperLapBattle 2020 COTA
Limited class winning lap on 285 Yokohama A052's

Xineering GCU - PPG Sequential 6 speed around COTA - Clutchless WOT Upshifts (Spark Cut) and Rev matched Downshifts(Blip)

Xineering Z06 - Daytona

2007 Corvette Z06 - Xineering GCU (Gearbox Control Module) with integrated DBW Blip Module Clutchless up and down shifts w/T56 Sequential transmission

Xineering Z06 - GCU Tuning

2007 Corvette Z06 - PPG T56 - Xineering GCU (Gearbox Control Module) WOT Shifting on the dyno