Holley
HOLLEY Ultra HP Carburetor - 750CFM
* Images may be a representation and may not reflect the actual product.
Product Details
Carburetor - Model 4150 - Ultra XP - 4-Barrel - 750 CFM - Square Bore - No Choke - Mechanical Secondary - Dual Inlet - Black Anodized - Each
Ultra XP Carburetor; 4 bbl; 750 cfm; 2 Circuit Metering; Model 4150UXP; Mech. Secondary; Gas; Dual Fuel Inlet; Dbl Accelerator Pump; Gray w/Blk Metering Block/Booster Inserts;
Xtreme Performance - Holley Ultra XP(TM) Circle Track Carburetors! Ultra XP carbs are 38% lighter than our original HP, have fuel capacity that is 20% greater and 30 other new features! They're available in our Hard Core Gray(TM) hard coat anodized finish with Black(TM) billet for improved corrosion protection & also available in natural tumble-polished aluminum with Black(TM) metering blocks and base plate. The Aluminum Ultra XP Cirlce Tracks are available in 650 & 750 CFM's. 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!
Fitment: Mechanical Secondary
DETAILS:
Part Number 0-80803HBX SPECS:
Carburetor - Ultra XP - Model 4150 - 4-Barrel - 750 CFM - Square Bore - No Choke - Mechanical Secondary - Dual Inlet - Aluminum - Black / Gray Anodized - Each
DETAILS:
- Holley Performance Emission Code 3: This part is legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles and Racing Use Only Vehicles. The following vehicles are considered Uncontrolled (Non-Emissions Controlled) Vehicles: 1965 and older U.S. manufactured California Certified vehicles/1967 and older U.S. manufactured Federally Certified vehicles/1967 and older Foreign manufactured vehicle. The following vehicles are considered Racing Use Only Vehicles: Racing Use Only Vehicles are vehicles that are used exclusively for competition and that are not registered and that may never be used on the street. WARNING: It is against the law to install this part on an Emissions Controlled Vehicle. The following vehicles are considered Emissions Controlled Vehicles: 1966 and newer U.S. manufactured California Certified vehicles/1968 and newer U.S. manufactured Federally Certified vehicles/1968 and newer Foreign manufactured vehicle
- Carburetor
- Ultra XP Carburetor
- 4 Corner Idle Allows You To Precisely Control Your Idle System
- 8AN O-Ringed Inlet Threads Offer A Variety Of Plumbing Options
- Air Bleeds Moved Outward For Smoother Transition Of Airflow
- Aluminum Construction
- Clear Sight Windows On Both Sides Of Bowls For Safe Fuel Level
- Contoured Venturi Inlet Balances Airflow For Increased hp
- Drain Plug On Bowl Provides Easy Access To Empty Bowl
- Dual 30CC Accelerator Pumps Fuel From Idle To Full Throttle
- Fuel Bowls Provide 20% More Fuel Capacity Controls Slosh
- Idle Bypass Valve Eliminates Holes In Throttle Plates
- Metering Blocks/True Gasket Sealing/Fully Adjustable
- Saves 4.5 Pounds 38% Weight Savings
- 4150 ALUM ULTRA XP 750 CFM (HARD BLACK)
- Carburetor
Part Number 0-80803HBX SPECS:
- Barrel: Four
- Billet Color: Hard Core Gray with Black
- Booster Type: Down Leg
- Carburetor Type: 4150
- CFM: 750
- Choke: None
- Circuit: 2
- Emission: Without EGR
- Finish: Hard Core Gray
- Flange: Square Bore
- Fuel Inlet: Dual
- Fuel Type: Gasoline
- Material: Aluminum
- Primary Main Jet: 76
- Primary Power Valve: 6.5
- Secondary Main Jet: 76
- Secondary Pump Nozzle Size: 32
- Secondary Type: Mechanical
- Supercharged Application: No
- Throttle Bore: 1.688 in.
- Type: Automotive
- Usage: Street/Hi-Performance
- Venturii Size: 1.376 in.
- WARNING CA Proposition 65 Message: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
- WARNING CA Proposition 65: Yes
Carburetor - Ultra XP - Model 4150 - 4-Barrel - 750 CFM - Square Bore - No Choke - Mechanical Secondary - Dual Inlet - Aluminum - Black / Gray Anodized - Each
Vehicle Fitment
Universal or product-specific fitment. Please review the product details and contact us if you need help confirming fitment before ordering.
Product Specs
- Brand
- Holley
- Part Number
- 0-80803hbx
- Catalog Number
- 001508582
- Product Line
- Carburetors
- Category
- Fuel Delivery
- Type
- Carburetors
- UPC / Barcode
- 090127713440
- Length
- 14.20 in
- Width
- 12.60 in
- Height
- 9.50 in
- Weight
- 9.25 lb
- Ship Alone
- No
- Air Restricted
- No
Shipping & Availability
This item is showing available inventory. Most in-stock performance parts ship quickly, but timing can vary by warehouse, vendor cut-off time, holidays, and carrier pickup.
Inventory shown: 2 available as of 6/3/2026.
Manufacturer warranty and return policy details will display here when available. Please refer to the manufacturers website for warranty information.
Reviews & Questions
Real product feedback when available, plus quick ways to get fitment or product help.
Other Popular Carburetors
A leader in fuel systems for over 100 years, Holley fuel management systems have powered top circle track and drag racing teams around the world. Now, Holley offers EFI systems for GM's LS engine, among many other applications. Holley's products also include performance fuel pumps, intake manifolds, and engine accessories products for street performance, race, and marine applications.
Review our return, cancellation, shipping, warranty, and product image policies before ordering.
Contact us with questions before ordering
California Residents: Prop 65 WARNING: This product MAY contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling. For more information, visit www.P65Warnings.ca.gov
California Residents: TIRE WARNING: LMPerformance will not ship Tires to California.
Legal: Some or all of these parts may not comply with Federal, State, Province, and/or Local laws, ordinances, and regulations. Buyer takes all responsibility to ensure that any modifications or upgrades that have done conform to all applicable laws and regulations for road use, especially pertaining to safety and emissions. LMPerformance is not responsible for buyer not complying with Federal, State, Province, and/or Local laws, ordinances, and regulations. This policy shall be in force for all past, current, and future purchases from LMPerformance, Inc. LMPerformance will not ship ANY non-CARB compliant products to California where California requires products to be CARB certified such as Catalytic Converters and Induction Kits.
Free Shipping: Please note FREE Shipping refers to shipping within the contiguous continental US only. All other locations extra. Some items that require Truck Freight Delivery will require a Truck Freight surcharge. This surcharge is still a discounted shipping amount that is lower then the actual truck freight shipping charge that is charged to LMP. LMP will try to still give the lowest price possible for truck freight items.
Images: Images may be a representation and may not reflect the actual product. Examples would be SPEC stage 3 clutch kits which all use the same photo.
TYPOS: LMPerformance tries to present the best most accurate information on our website. Sometimes we get mistakes in product information sent from vendors such as typos. We can not be responsible for these typos, if you see something that does not look right please let us know before ordering so we can double check for you first. LMPerformance will not pay for typos in any way, monetarily or otherwise.
Price Errors: In the event that a product has mistakenly been listed at an incorrect price, We reserve the right to refuse or cancel any orders placed for product listed at the incorrect price. We reserve the right to refuse or cancel any such orders whether or not the order has been confirmed and your account charged. If your payment type has already been charged for the purchase and your order is cancelled, a full refund to your orignial payment method in the amount of the incorrect price will be issued.
Special Order ITEMS: Some items are Special Ordered and may not be returnable, or even cancellable as they are going into production specifically because you ordered them. Special Ordered items can have a 5-35% cancelation fee.
Cancellations: Instock orders cannot be canceled due to our automated ordering & fast shipping system. To keep our prices low, all cancelations are subject to a 5% cancelation fee to cover transaction processing fees. We reserve the right to charge up to a 10% cancellation fee for cancelled orders due to merchant fees, Special Order fees and the cost of processing and shipping orders.When you request a cancellation of an order or a part, please note that it may take time for a manufacturer to cancel an order if the order is drop-shipped. We also have to confirm that the product has not shipped. If the product has shipped then this must be processed as a return.Also note that sometimes products ship more quickly than expected, so we recommend that you do not purchase alternative products until receiving final confirmation of the cancellation.
Returns: We cannot accept returns on parts that have been used or installed. No returns will be accepted after 30 days. All Returns must be in original packaging. Prior authorization must be given before any return can be made. Up to a 25% Restocking Fee may apply. Special Orders may be subject to Additional Manufacturer Restock Fees as well. Shipping cost will not be refunded.Hoods as well as PCM Programmers may not be returned unless defective and only for replacement. ALL returns must be first filed using our online form found here: https://www.lmperformance.com/returns.
Lost Order Claims All lost order/package claims must be made within 5 days of the shipping date or tracking information delivery date. All claimes made after this date will not be accepted due to Shipping companies policies of filing loss claims.
Damaged Items or Incorrect Items: Please contact us right away if your item has been damaged in shipping or are incorrect. Please note that we will ship replacement items the same method of shipping the order was originally placed for. LMPerformance can not ship packages overnight at our cost if the original shipping was not also overnight. Claims must be filed in order for replacement parts to be shipped.
Warranties:Any warranty claims must be placed with the manufacturer. All of the products sold by LMPerformance, regardless of the manufacturer, are designed for Racing and Performance applications. Many of our manufacturers offer NO WARRANTY on their products, either stated or implied, due to the unusual stresses placed on the parts and because we have no control over how they are installed and used. Many of these products are designed for off-road use only and are not legal for use on public highways. If you have a question about the warranty on a specific product, please e-mail or call us. Buyer assumes all risk and liability associated with these products.
Installation: We are not responsible for or any costs associated with the installation or the improper installation of any products. Purchaser assumes the risk associated with the installation of products. We, along with the manufacturer of each product are not responsible for any direct or indirect damage to the vehicle, personal, or costs incurred from the use of products.