Racepak The Racepak OBDII to EFI adapter provides the ability to adapt the CL2 for use with a variety of aftermarket standalone EFI systems. The OBDII to EFI Adapter allows streaming and recording of up to 17 data channels from select CAN based EFI systems. The adapter plugs into the OBDII port on the CL2 unit, and an EFI cable specific to the EFI system (sold separately) connects to the adapter plug. Power and ground connections are made with the adapter's red and black wires.