Which intake manifold should you choose? Holley and other manufacturers offer a wide array of single- and multiple-carb manifolds. In basic terms, if you want low-end torque at lower engine RPM, consider a dual-plane intake manifold. Single-plane manifolds tend to favor upper-end power at higher engine speeds. A very broad generalization is to select a […]

When you are ready to reassemble the carburetor, all parts must be clean and free of any contaminant and gasket residue. Rather than guessing at fastener tightening, use a calibrated in-lb torque wrench and follow all torque specifications.   This Tech Tip is From the Full Book, HOLLEY CARBURETORS: HOW TO REBUILD. For a comprehensive […]

Carburetor cleanliness is absolutely critical. Any small particles such as dirt, sand, etc. can easily clog small ports and passages. Buildup of carbon, old grease, and so on can hinder movement of shafts and other moving parts. During any service or rebuild, take the time to ensure that every single component is absolutely clean and […]

If you plan to disassemble a carburetor, it should be done with the carburetor removed from the intake manifold and placed on a clean workbench. To make the carb more stable, place it on a stand that supports the carb by its baseplate-to-manifold mounting holes. This also makes the disassembly job much easier.   This […]

Carburetor service requires a selection of conventional hand tools as well as a select number of specialty tools. Many specialty tools are available from Holley as well as popular aftermarket suppliers, such as Summit Racing and Jegs. Having all of the tools listed here prior to beginning service makes your work more efficient and less […]

Selecting the right carburetor for a given engine and vehicle combination can seem confusing. The first order of business is to choose the appropriate airflow capacity, or CFM (cubic feet per minute), especially if your goal is to maximize horsepower. Remember the old adage, “bigger is not always better.” If a carburetor is too small […]

Holley 4-barrel carburetors are dual-stage, downdraft units. A dualstage carb has a primary side that supplies the air/fuel mixture throughout the entire stage of engine operation, and a secondary side that operates only when the engine demands a greater quantity of air and fuel.   This Tech Tip is From the Full Book, HOLLEY CARBURETORS: […]

The 1950s saw the introduction of the Holley Series 4150 4-barrel on the 1957 Thunderbird. It was the beginning of the modular Holley 4-barrel, as we know it today. It was the first true performance carburetor and it became standard equipment on many high-performance automobiles.   This Tech Tip is From the Full Book, HOLLEY […]