Holley 0-80845HBX Ultra XP Carburetor

The Holley Ultra XP Carburetor (0-80845HBX) is a 950 CFM 4-barrel mechanical-secondary race carburetor with an E85-specific calibration, finished in Hard Core Gray hard-coat anodize with Black billet metering blocks and base plate. Up to 38% lighter than traditional race carburetors thanks to all-aluminum construction. Features elongated dual-pattern mounting holes that allow installation on either Holley 4150-style square flange or Holley Dominator-style large flange manifolds, making this a versatile choice for drag race, circle track, or any high-horsepower application.
Features:
950 CFM, 4150-style 4-barrel with mechanical secondaries
E85-specific calibration
All-aluminum construction (saves 4.5 lbs - 38% weight savings)
Hard Core Gray with black anodized billet aluminum metering blocks and booster inserts
Designed for drag race, circle track, or any high-horsepower engines
Contoured venturii inlet for balanced airflow and increased horsepower
Air bleeds moved outward for a smoother transition of airflow into the venturii
Fully adjustable metering blocks with true gasket sealing (emulsion bleeds, power valve channel restrictors, idle feed restrictors)
Integrated idle bypass valve maintains correct throttle plate to transfer slot relationship - good for radical camshafts
Fuel bowls provide 20% more fuel capacity with internal baffling to control slosh
Clear sight windows on both sides of the bowls
Built-in drain plug in front center of the bowl
-8AN O-ring inlet threads, can be plumbed from either side
Elongated (dual pattern) mounting holes - fits both Holley 4150 and Dominator flanges
Knurled (hand adjustable) primary and secondary curb idle screws
Capped primary throttle shaft to prevent debris entry
Factory machined accessory mounting hole for an adjustable primary throttle stop
Stainless steel adjustable secondary link - 1:1 or progressive secondary actuation

• Barrel Quantity: 4
• Barrels: 4
• Billet Color: Hard Core Gray with Black
• Body Color: Hard Coat Gray
• Body Finish: E-Coated
• Body Material: Aluminum
• Booster: Downleg
• Booster Design: Downleg
• Brand: Holley
• Carburetor Material: Aluminum
• Carburetor Use: Professional Race
• Category: Air and Fuel Delivery
• CFM Rating: 950
• Choke: None
• Choke Type: None
• Color: Hard Coat Gray
• Condition: New
• Cubic Feet Per Minute Rating: 950
• Emission Code: 3
• Finish: Hard Core Gray
• Flange Shape: Square
• Flange Type: 4150/4500
• Fuel: E85
• Fuel Inlet: Dual
• Fuel Type: E85
• Grade Type: Performance
• High Speed Air Bleed: 24
• Idle Air Bleed Size: 67
• Linkage Attached: Yes
• Marine Approved: No
• Material: Aluminum
• Model: 4150
• Mounting Hole Quantity: 4
• Part Type: Carburetor
• Primary Jet Diameter: 96
• Primary Main Jet Size: 96
• Primary Power Valve: 5.5
• Primary Pump Nozzle Size: 42
• Product Type: Carburetor
• Secondary Barrel Type: Mechanical
• Secondary Main Jet Size: 106
• Secondary Pump Nozzle Size: 50
• Spacer Included: No
• Sub Category: Carburetion
• Supercharger Compatible: No
• Throttle Bore Diameter: 1.750 inch
• Venturii Size: 1.600 inch
• Warning: California Proposition 65
• Warranty: Manufacturer's Limited 90 Day Warranty