06 We mounted our fuel pressure regulator to the inner fender on the passenger side of the engine bay, and connected it to the fuel supply line we'd run from the back of the car. Note that we chose nylon braided fuel line for our Challenger. It's NHRA legal just like steel braided line, but won't give you puncture wounds or jam under your fingernails while installing the fittings. Although we'll initially be running a single four-barrel on this engine, Holley's four-port billet fuel pressure regulator will allow us to test dual-quads on this engine at a future date if we desire. This regulator has a single -8 AN inlet and four -6 AN outlets.