HOLLEY 500 CFM ULTRA XP 2BBL carburettor

Description

The original Holley 0-4412 has powered thousands of racers to the winners’ circle! How do you make it better? Add the proven design elements of the popular Ultra series for more tunability, more durability, more weight savings and more features! The Ultra XP 2bbl carburettors feature all aluminium construction for nearly 50% weight savings over their zinc counterparts, contoured venturii inlet for unobstructed airflow, screw in air bleeds for easy fine tuning, black anodised fully adjustable billet aluminium metering block and baseplate, high capacity fuel bowl which features 20% more fuel capacity to eliminate starvation, integrated fuel shelf to minimize fuel aeration and internal baffling to control fuel slosh and a centered air cleaner flange for improved airflow and performance. Other notable features include wedged floats, knurled hand adjustable curb idle screw and down leg boosters. Ultra XP 2bbl carburettors are approved for use in NASCAR Mid-West/West Coast Late Model Divisions and utilize the same venturii and throttle bore dimensions of the classic 4412 2bbl carburettor. Available in shiny or Hard Core Gray finishes, the Ultra XP 2bbl will outperform any production 2bbl available.
Features:
All aluminium construction – for nearly 50% weight savings over zinc version
Tumble polished aluminium with Black billet aluminium metering block and base plate
No choke tower for unobstructed airflow
Air bleeds moved outward to allow a smoother transition of airflow
Air cleaner flange centered over venturii for improved airflow and performance. 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 metering block equipped with tunable bleed off
Same 1-3/8” Venturii & 1-11/16” Throttle Bore size and Throttle Plate/Throttle Shaft size of original 0-4412
Fuel bowl provides 20% more fuel capacity while controlling slosh with internal baffling
Clear sight windows on both sides of bowl for easy & safe fuel level adjustments
Fuel trough designed into floor of bowl to route fuel flow directly to the jets and assists in keeping jets covered by fuel
Built in drain plug provides easy access to empty contents of bowl
-8 (O-ring) inlet threads offer a large variety of plumbing options (come with an extended -8 O-ring to -8AN male adapter and -8 plug). Can be plumbed from either side
Throttle shaft rides in oil impregnated sintered bronze bushings for smooth throttle actuation
Throttle shaft capped to prevent entry of debris & contaminates
30cc pump with metal lever. Anti-siphon valve in mainbody to reduce pump pull over
Dedicated race-only throttle lever with all unnecessary street attachment points & tangs removed
Knurled (hand adjustable) curb idle screw allows for easy idle adjustment without the use of tools
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!