New Holley Ultra HP 2 Barrel Carbs

holley carburetorHolley carbs have powered more racers than all others combined and they've just changed the game again. Holley is proud to introduce the all new Ultra HP 2 Barrel.  Holley 2 barrels have been a mainstay in oval track racing for decades, but racers always want more.  They want more tuning ability, more durability, more weight savings and more features, so Holley listened and designed the all new Ultra HP 2bbl.
It delivers the proven results of the Ultra HP 4bbl but now in a 500 CFM 2bbl. It’s all aluminum so it provides nearly 50% weight savings. It has no choke tower and an all new air entry area for smoother air flow, yet it retains the critical venturii and throttle bore dimensions for rule racing.  It has large capacity HP fuel bowls, wedged float, dedicated race-only throttle lever, billet metering blocks & base plates, plus much more.  The new Ultra HP 2bbl carbs are available in two finishes – a vibratory polished with black billet (part number 0-4412BK) and a Hard Core™ Gray hard coat anodized with black billet (part number 0-4412HB). They are already approved for use in the NASCAR Mid-West/West Coast Late Model Divisions and Holley expects more sanctioning bodies to approve them soon.

Note: Click the adjacent flyer image for further details.

holley carburetorFeatures:
  • All aluminum construction - for nearly 50% weight savings over zinc version
  • No choke tower for unobstructed airflow
  • Machined venturii throat for consistent carb to carb performance and at track gauging
  • Tumble polished aluminum with Black™ billet
  • Billet aluminum metering block for improved durability, true gasket sealing, good looks
  • 6061T6 Billet aluminum baseplate
  • Throttle shaft rides in oil impregnated sintered bronze bushings for smooth throttle actuation
  • Slash-cut vent tube
  • Contoured hex head squirter screw for streamlined airflow
  • Same 1-3/8” Venturii & 1-11/16” Throttle Bore size and Throttle Plate/Throttle Shaft size of original 0-4412
  • 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
  • Knurled (hand adjustable) curb idle screw allows for easy idle adjustment without the use of tools
  • Set screw for wide open throttle stop adjustment
  • Dedicated race-only throttle lever with all unnecessary street attachment points & tangs removed
  • Fuel shelf below the needle and seat to greatly minimize fuel aeration and promote more consistent metering
  • Internal baffling to help control fuel slosh and minimize float level fluctuations in hard launching or cornering situations
  • Clear sight windows on both sides of bowl for easy & safe fuel level adjustments
  • Internal pump passage on metering block equipped with tunable bleed off
  • Fuel trough designed into floor of bowl to route fuel flow directly to the jets and assists in keeping jets covered by fuel
  • 30cc pump with metal lever. Anti-siphon valve in mainbody to reduce pump pull over
  • Throttle shaft capped to prevent entry of debris & contaminates
  • 20% more fuel capacity vs. a traditional v-bowl - eliminates fuel starvation and provides consistent air/fuel ratios
  • Wedge float provides fuel control while cornering
  • 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
  • Approved for use in NASCAR® Mid-West/West Coast Late Model Divisions (NASCAR is a registered trade mark of the National Association of Stock Car Auto Racing, Inc.)



Holley Tech Service
P.O. Box 10360
Bowling Green, KY., 42101-7360
Telephone 270-781-9741