Holley Aluminum Ultra XP 2-Barrel Carburettor CFM 500 2-barrel Black
Holley aluminum Ultra XP 2-barrel carburetors feature all-aluminum construction for nearly 50 percent weight savings over the standard zinc version. They use a billet aluminum metering block for improved durability and true gasket sealing; and a billet aluminum base plate with dedicated race-only throttle lever (all unnecessary street attachment points and tags removed). The throttle shaft is capped to prevent entry of debris and contaminates, while a knurled curb idle screw allows easy idle adjustment without the use of tools; a set screw provides wide open throttle stop adjustment. The new fuel bowl provides 20 percent more fuel capacity than traditional V-bowls--with a wedge float for fuel control, a built-in drain plug for quick jet changes, clear sight windows on both sides for easy float level adjustments, and -8 AN inlet threads that can be plumbed on either side. The fuel trough is positioned in the floor of the bowl to route fuel directly to the jets and minimize fuel aeration, while promoting more consistent metering. Up on top of the Holley aluminum Ultra XP 2-barrel carburetors we find the choke horn has been removed; the air cleaner flange is now centered over the venturi for improved airflow performance; downleg boosters provide improved fuel signal into the 1 3/8 in. venture; a contoured head squirter screw streamlines air flow; and the air bleeds have been moved outward to allow a smoother transition of airflow. The carburetors are available in your choice of tumble polished finish, with black anodized metering block and base plate; or, hardcore gray anodized, with black anodized metering block and base plate.
