HOLLEY L12R56 Billet Base Plate Double Pumper Idle 4-CORNER

( Brand: Holley ), ( Type: Throttle Body, Base Plate ), ( Manufacturer Part Number: L12R56 ), ( Material: Aluminum ), ( Country Of Origin: United States ), ( Performance Part: Yes )

Review HOLLEY Genuine Red Billet Base Plate Double Pumper Idle fits 650 750 800

The Holley L12R56 Billet Base Plate is a high-performance carburetor component designed for use with Holley 650, 750, and 800 double pumper 4-corner idle applications. This billet base plate is manufactured using 6061-T6 aluminum, which provides superior strength and durability compared to cast base plates. The CNC-machined surface ensures a perfect fit and finish, while the billet construction allows for greater customization and flexibility in terms of mounting and modification options.

This base plate features a 12-inch overall length and a 56-inch bore circle, making it suitable for use with larger engines and applications that require increased fuel delivery. The 4-corner idle design allows for precise idle control, ensuring stable and consistent engine performance. The billet base plate is also compatible with Holley's electronic fuel injection systems, making it an excellent choice for modern hot rods and high-performance applications.

The L12R56 Billet Base Plate comes with several mounting options, including four mounting bosses for use with standard Holley mounting hardware, as well as two additional bosses for use with accessory brackets or other custom mounting solutions. The plate also includes pre-drilled holes for vacuum and fuel pressure gauge installations, making it easy to monitor engine performance and optimize fuel delivery.

Overall, the Holley L12R56 Billet Base Plate is a high-quality, customizable component that offers superior performance and versatility for Holley 650, 750, and 800 double pumper 4-corner idle applications. Its billet construction, CNC-machined surface, and compatibility with electronic fuel injection systems make it a top choice for serious performance enthusiasts and hot rod builders.

The Holley L12R56 billet base plate 4-corner idle system is a performance fuel injection solution designed for high-performance applications. This system is suitable for engines with displacements between 650 and 800 cubic inches (10.6L to 13.2L) and can be used with both EFI and carbureted applications. In this analysis, we will outline the potential advantages and disadvantages of investing in this Holley product.

1. Improved Idle Stability: The 4-corner idle system offers enhanced idle stability, which is crucial for high-performance engines that require consistent engine speed for optimal operation.

2. Versatility: The L12R56 billet base plate can be used with both EFI and carbureted applications, making it a versatile choice for various engine setups.

3. High-Quality Construction: The billet aluminum base plate and high-performance fuel pumps ensure durability and reliability, making it a suitable choice for high-performance applications.

4. Easy Installation: Holley provides detailed instructions and a user-friendly installation process, making it easier for enthusiasts and professionals to install the system on their engines.

5. Adjustability: The 4-corner idle system offers adjustability for fine-tuning the idle speed, ensuring optimal engine performance.

1. Cost: The Holley L12R56 billet base plate 4-corner idle system is a premium product, and its cost may be prohibitive for some enthusiasts and budget-conscious builders.

2. Complexity: While the installation process is user-friendly, the system itself can be complex, requiring a good understanding of fuel injection systems and engine tuning.

3. Compatibility: Ensure the system is compatible with your specific engine setup before making a purchase, as some modifications may be necessary for proper installation.

The Holley L12R56 billet base plate 4-corner idle system offers numerous advantages, including improved idle stability, versatility, high-quality construction, easy installation, and adjustability. However, it comes with a premium price tag and requires a certain level of knowledge and understanding to install and optimize the system.

If you are building a high-performance engine and seeking improved idle stability, the Holley L12R56 billet base plate 4-corner idle system is an excellent choice. Its versatility, durability, and ease of installation make it a worthwhile investment for enthusiasts and professionals alike. However, ensure that you have a solid understanding of fuel injection systems and engine tuning before making a purchase, or consider seeking professional assistance to optimize the system for your engine setup.

part # l12r56 prices

• $95.90-$128.99

specifications carbcaddie:

• for models: 650, 750, 800
• brand: Holley
• type: Throttle Body, Base Plate
• manufacturer part number: L12R56
• material: Aluminum
• country of origin: United States
• performance part: Yes

payments carbcaddie:

• other
• check
• wallet: Paypal
• money order
• cash
• credit card: Diners-club

seller carbcaddie:

• rating: 100.0%
• # reviews: 3507

returns carbcaddie:

• policy: Returns Accepted
• time: 30 Days
• paid by: Seller

general carbcaddie:

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

shipping carbcaddie:

• type: Calculated
• class: Standard
• transit: 3-7 Days
• cost: $16.45
• service: USPS Ground Advantage
• carrier: USPS

offer carbcaddie:

• options: Ship-to-home
• started: April 28, 2026
• sold: 0
• quantity: 10
• availability: In Stock

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