Stage 4


At power levels over 600bhp the standard fuel injectors will be at 100% duty so the stage 4 kit features our larger 1,100cc injectors to ensure the engine receives the correct amount of fuel. These Bosch Motorsport based injectors have a superb spray pattern so fuel consumption and driveability are as good, if not better, than the standard OEM 570cc injectors. These are the same injectors we use in our 800bhp conversions.

Like the Stage 3 upgrade it also features the Milltek Y-pipe, exhaust system, large bore intake kit and a new ECU calibration for the larger injectors.

The Stage 4 Power upgrade includes:


  • Litchfield 1,100cc Bosch Injectors
  • Litchfield Large Bore performance intake kit with larger MAF housing
  • Milltek Y-Pipe
  • Milltek rear exhaust system
  • Exhaust back pressure reduced by over 37%
  • Improved boost control with custom Ecutek code
  • Revised ignition control, Variable Valve timing and Fuel maps
  • Reduced fuel consumption (especially on partial throttle conditions)
  • Increase in both power and torque across the whole rev range
  • Litchfield RACEROM Switchable maps for enhanced Economy mode and full Race mode
  • Litchfield Custom Launch Control settings when used with Gearbox Software upgrade

The Stage 4 package costs £4,249 fitted inc. VAT

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