Use with Terminator X or Terminator X Max Only. 2009+ Gen III Hemi engines rolled off the showroom floor with Variable Valve Timing (VVT). Now, both Terminator X and Terminator X Max ECUs will allow you to control and tune the VVT with the use of the plug and play VVT harness.. Requires Terminator X Firmware and Software V2 Build 50 (Terminator X V2.0.50 Software).