Lightweight Ceramic Valve, Hard Anodized Billet, .250” Orifice
The Race Pumps fuel pressure regulator installs between the fuel pump and the carburetor.
The lower port is -8 AN O-ring, this is the inlet from the fuel pump.
The side ports are -8 AN O-ring, these are outlet ports to the carburetor. You may use just one or both of these ports.
The -4 idle bleed must be returned to the fuel cell.
The #70 jet in the idle bleed will reduce idle pressure by 2-4 pounds. The Race Pumps regulator is much smoother than other designs, so the idle pressure does not need to be reduce as much to allow the engine to idle smooth. Most methanol carburetors will idle good at 8 PSI with the Race Pumps regulator. Installing a larger jet is not recommended.
The 1/8” barbed fitting may be used as a vent by installing a short piece of vacuum hose to a clean/dry area.
Plumbing the 1/8” barbed fitting to a vacuum port below the carburetor base plate will reduce fuel pressure at high RPM off throttle conditions (corner entry). This will make the engine “cleaner” when you pick up the throttle on corner exit. Idle pressure will also be reduced.
The socket head set screw on the top of the regulator adjusts the fuel pressure. Screwing it in increases fuel pressure, out decreases fuel pressure. Set the fuel pressure with the engine running at 1500 RPMs with the vacuum hose disconnected. Most carburetors work well with 7 PSI on gasoline and 9 PSI on methanol.