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

Haltech Fuel Injector Adapter - 14mm 1/2 to Full Length

Haltech Fuel Injector Adapter - 14mm 1/2 to Full Length

$12.60

FAST Electric Fan and Fuel Pump Harness for XFI

FAST Electric Fan and Fuel Pump Harness for XFI

$189.04

FAST XFI Fuel Injector Y Adapter Harness for Multiple Injectors

FAST XFI Fuel Injector Y Adapter Harness for Multiple Injectors

$325.21

FAST XFI Accelerometer Kit

FAST XFI Accelerometer Kit

$600.12

FAST Wiring Harness, Fast 4-Cyl Fue L Injector

FAST Wiring Harness, Fast 4-Cyl Fue L Injector

$215.71