Holley 0-80812HBX Ultra XP Circle Track Carburetor, 650 CFM, Gray

Holley Ultra XP Circle Track carburetors are 38% lighter than the original HP, have fuel capacity that is 20% greater and 30 other new features! Holley Ultra XP Carburetors are specifically calibrated for Circle Track & offer new features such as anti-siphon valve in the main body; high capacity HP bowls which feature 20% more fuel capacity to eliminate starvation, integrated fuel shelf to minimize fuel aeration and internal baffling to control fuel slosh. Other features include all aluminum construction, fully tunable billet metering blocks, billet base plate, wedge floats, adjustable secondary linkage and knurled (hand adjustable) curb idle screws. Holley Ultra XP carburetors are the ultimate in square bore race carburetors!

• Hardcore Gray with black anodized billet aluminum metering block and booster inserts
• Calibrated specifically for use on circle track
• Has a set screw in the base plate for wide open throttle stop adjustment
• PTFE coated throttle shafts rides in oil impregnated bronze bushings for smooth throttle actuation
• Anti-siphon valve in main body to reduce pump pullover
• Contoured venturri inlet offers balanced airflow for increased horsepower
• Air bleeds moved outward to allow a smoother transition of airflow from the top of the carburetor into the venturii
• Dual 30cc accelerator pumps provide the perfect amount of fuel from idle to full throttle
• Fuel bowls provide 20% more fuel capacity while controlling slosh with internal baffling
• Clear sight windows on both sides of bowls for easy and safe fuel level adjustments
• Built in drain plug in front center of bowl provides easy access to empty contents of bowl
• -8 (o-ringed) inlet threads offer a large variety of plumbing options and can be plumbed from either side; comes from the factory with 8AN inlet fittings
• 4 corner idle allows you to precisely control your idle system
  Internal pump passage in metering block equipped with a tunable bleed off for further tuning of accelerator pump
• Factory machined accessory mounting hole for easy addition of adjustable primary throttle stop. New secondary pump cam lever designed to provide positive throttle stop on secondary side
• Set up with 1:1 throttle actuation
• Baseplate designed with a boss that can be consumer machined for vacuum source
• Includes wedge floats
• 100% wet-flow tested by Holley technicians to assure it arrives ready to run

Installation Instructions (PDF)