Aem high volume fuel rails feature a 1/2-inch fuel bore to support fuel flow for applications up to 1,000 horsepower. this large bore also dampens backpressure pulses created by larger injectors and works perfectly with stock injector sizes. an additional 1/8th npt port is included to accommodate a nitrous set up or fuel pressure gauge. a custom fuel line fitting is included for the factory fuel line, and the ends of each rail are pre tapped to accept -6 an or 9/16”x18 fittings for users who want to use custom fuel lines.