Performance car owners want fuel economy and throttle response. That's why they upgrade to the EZ-EFI fuel pump conversion for mpg improvement. FAST has the relay harnesses to compliment this system. These plug-and-play harnesses are simple to install, and they'll hook you up to the precise amount of fuel for optimal performance.

More From This Category

FAST XFI 2.0 Main Harness For Ford Mustang Cobra Jet

FAST XFI 2.0 Main Harness For Ford Mustang Cobra Jet

$3,205.79

FAST Wiring Pigtail, Early/TPI MAP Sensor to Metripack/LS Harness Adapter, Each

FAST Wiring Pigtail, Early/TPI MAP Sensor to Metripack/LS Harness Adapter, Each

$41.20

FAST XFI Fuel Injector Harness for SBC, BBC, LT1 and For Chrysler Small Block, B and RB

FAST XFI Fuel Injector Harness for SBC, BBC, LT1 and For Chrysler Small Block, B and RB

$336.53

FAST XFI Calibration Switch Kit

FAST XFI Calibration Switch Kit

$84.62