Holley 4412XP CT 500 CFM Stage 3 Series 2-Barrel Carburetor

Carburetor, New — Holley 4412XP CT 500 CFM Stage 3 Series, 2-Barrel, Square Bore, Single Feed. The metering plate mounting surface has been milled for a better gasket seal. The original Holley 0-4412 has powered thousands of racers to the winners’ circle. The Ultra XP 2bbl improves on it with the proven design elements of the popular Ultra series for more tunability, durability, weight savings and features. It uses all-aluminum construction for nearly 50% weight savings over its zinc counterpart, a contoured venturii inlet for unobstructed airflow, screw-in air bleeds for easy fine tuning, a black anodized fully adjustable billet aluminum metering block and baseplate, a high-capacity fuel bowl with 20% more fuel capacity to eliminate starvation, an integrated fuel shelf to minimize aeration, internal baffling to control fuel slosh, and a centered air-cleaner flange for improved airflow. Other notable features include wedged floats, a knurled hand-adjustable curb-idle screw and down-leg boosters. Approved for use in NASCAR Mid-West / West Coast Late Model Divisions, it utilizes the same venturii and throttle-bore dimensions as the classic 4412 2bbl and will outperform any production 2bbl available. Features: All-aluminum construction for nearly 50% weight savings over the zinc version. Tumble-polished aluminum with Black billet aluminum metering block and base plate. No choke tower for unobstructed airflow. Air bleeds moved outward for a smoother transition of airflow. Air-cleaner flange centered over the venturii for improved airflow and performance, with a 5/16-18 bent air-cleaner stud included. Down-leg boosters for improved fuel signal. Contoured hex-head squirter screw for streamlined airflow. Internal pump passage on the metering block equipped with tunable bleed-off. Same 1-3/8 in. venturii and 1-11/16 in. throttle bore, throttle plate and throttle shaft as the original 0-4412. Fuel bowl provides 20% more capacity while controlling slosh with internal baffling. Clear sight windows on both sides of the bowl for easy, safe fuel-level adjustment. Fuel trough designed into the floor of the bowl routes fuel directly to the jets and helps keep them covered. Built-in drain plug for easy bowl draining. -8 O-ring inlet threads offer a large variety of plumbing options (includes an extended -8 O-ring to -8AN male adapter and -8 plug) and can be plumbed from either side. Throttle shaft rides in oil-impregnated sintered bronze bushings for smooth actuation and is capped to prevent debris entry. 30cc pump with metal lever and an anti-siphon valve in the main body to reduce pump pull-over. Dedicated race-only throttle lever with unnecessary street attachment points and tangs removed. Knurled hand-adjustable curb-idle screw for tool-free idle adjustment. Set screw for wide-open throttle stop adjustment. Wedge float provides fuel control while cornering. 100% wet-flow tested by Holley technicians to assure it arrives ready to run. CJR Performance Carburetor ships carburetors only after they have been thoroughly run-tested and adjusted on a typical engine. Engine testing all carburetors prior to shipment ensures that when a new CJR carburetor is bolted on an engine, it will start, idle, and perform up to the customer’s expectations. However, sometimes a little more fine-tuning is necessary because the customer has a fairly radical street setup with a big cam and lower-than-typical intake vacuum, or the carburetor is not properly sized for the engine it is being used on. Before starting your engine, tighten all bolts and screws — there can be substantial gasket shrinkage after the carburetor has been fired up. Set all float levels 25% up from the bottom of the glass, and make only light passes until you verify the jetting is within the engine’s requirements. Most gasoline carburetors require a minimum of 7.25 psi of fuel under load at wide-open throttle to perform appropriately, and the boosters should not drip fuel at idle.