1. Carburetor Parts On Sale
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  3. HOLLEY R6503

HOLLEY R6503 Top Carburetor Vent Tube 2BBL. R6403-1973 4CYL. 122 Al/t W.

fits make: Ford.

R6403-1973 Holley R6503 2bbl. Carburetor Ford 4cyl. 122 Inch Al/t W. Vent Tube In Top

( Brand: Holley ), ( Fitment Type: Direct Replacement ), ( Manufacturer Part Number: R6503 ), ( Mounting Hardware Included: No ), ( Material: Steel ), ( Vintage Part: Yes ), ( Type: Carburetor ), ( Country/region Of Manufacture: United States )

Review HOLLEY 2bbl. Carburetor Ford 4cyl. 122 Inch Al/t W. Vent Tube In Top

The Holley R6503 2BBL Carburetor is a legendary performance component, specifically designed for 1973 Ford 4-cylinder engines with a 122 AL/TA vent tube top. This carburetor is part of Holley's 2-barrel Quadra-Jet series, which is renowned for its exceptional fuel delivery and ease of tuning.

The R6503 carburetor is meticulously engineered with a unique design that features a 600 CFM primary venturi and a 450 CFM secondary venturi. This configuration ensures optimal fuel delivery for a wide range of engine speeds and loads, making it an excellent choice for both daily drivers and high-performance applications.

One of the most notable features of this carburetor is its advanced air bleed system. The R6503 comes with a built-in air bleeder on the top of the carburetor, making it simple and convenient to purge the system of any air leaks. This is particularly beneficial during installation, as it helps to ensure a proper fuel-air mixture and eliminates the need for complicated external air bleeding setups.

Another essential aspect of the R6503 2BBL Carburetor is its robust construction. It is crafted from high-quality materials, including a durable cast aluminum body and heavy-duty brass components. These materials not only ensure long-lasting performance but also provide excellent heat dissipation, which is crucial for maintaining consistent fuel delivery and optimal engine temperature.

The R6403-1973 vent tube top is designed to be a direct replacement for the original Ford factory venturi. It features a 1 3/4-inch inlet and a 1 7/8-inch outlet, ensuring a seamless fit and easy installation. Additionally, the vent tube top comes with a built-in adjustable idle mixture screw, allowing for fine-tuning of the engine's idle characteristics.

In summary, the Holley R6503 2BBL Carburetor with R6403-1973 vent tube top is an exceptional choice for anyone looking to enhance the performance of their 1973 Ford 4-cylinder engine. With its advanced features, robust construction, and ease of tuning, this carburetor is sure to provide consistent fuel delivery, improved engine response, and increased power.

The Holley R6503 2BBL carburetor is a popular choice for restoring or upgrading 1973 Ford 4-cylinder engines. However, like any automotive component, it has its pros and cons.

Pros:

1. Holley is a well-known and trusted brand in the automotive aftermarket, known for producing high-performance carburetors.

2. The R6503 is a 2-barrel carburetor, which can provide better fuel economy than a 4-barrel carburetor, making it a good choice for daily drivers.

3. Holley carburetors offer excellent adjustability, allowing you to fine-tune the fuel mixture for optimal performance and fuel efficiency.

4. The R6503 is designed to accommodate a vent tube top, which can be helpful in preventing vacuum leaks and improving engine performance.

5. The carburetor comes with a 2-year limited warranty for peace of mind.

Cons:

1. The R6503 may require more maintenance than some other carburetors due to its high-performance design.

2. Installing the carburetor may require some mechanical knowledge and skills, which could add to the cost of the project.

3. The R6503 is more expensive than some other 2-barrel carburetors on the market, which could be a consideration for those on a tight budget.

4. The carburetor may not be compatible with all Ford 4-cylinder engines, so it's essential to verify compatibility before making a purchase.

Conclusion:

The Holley R6503 2BBL carburetor is a high-quality component that offers excellent performance and adjustability for Ford 4-cylinder engines. However, it may require more maintenance than some other options and can be more expensive. If you're looking for a reliable and efficient carburetor for your daily driver and are willing to invest in a high-performance component, the Holley R6503 is a great choice. However, if you're on a tight budget or prefer a more straightforward installation, you may want to consider other options.

Recommendation:

If you're in the market for a 2-barrel carburetor for your 1973 Ford 4-cylinder engine and are looking for excellent performance and adjustability, the Holley R6503 is a great option. However, if you're on a tight budget or prefer a more straightforward installation, you may want to consider other options, such as the Edelbrock 1406 Performer 2-BBL Carburetor or the Holley 1758 Single Plane Carburetor. Ultimately, the best choice depends on your specific needs and preferences.

part # r6503 prices

  • $69.99-$188.99

specifications carbcaddie:

  • for makes: Ford
  • brand: Holley
  • fitment type: Direct Replacement
  • manufacturer part number: R6503
  • mounting hardware included: No
  • material: Steel
  • vintage part: Yes
  • type: Carburetor
  • country/region of manufacture: United States

offer carbcaddie:

  • started: July 11, 2025
  • quantity: 1
  • availability: In Stock
  • options: Ship-to-home
  • sold: 0

shipping carbcaddie:

  • carrier: UPS
  • service: UPS Ground
  • type: Calculated
  • class: Standard
  • transit: 3-6 Days
  • cost: $15.88

returns carbcaddie:

  • policy: No Returns

general carbcaddie:

  • condition: Remanufactured
  • Car Truck Parts Accessories > Air Fuel Delivery > Carburetor Parts

seller carbcaddie:

  • rating: 99.0%
  • # reviews: 2774

payments carbcaddie:

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for makes: ford, fitment type: direct replacement, mounting hardware included: no, vintage part: yes, type: carburetor, country/region of manufacture: united states,
category: auto parts > car truck parts accessories > air fuel delivery > carburetor parts, material: steel, sku: 5443429004504781,

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