Primary Metering Block

The Holley Primary Metering Block (HLY134-128) is a vital component for regulating fuel delivery in carbureted engines, making it essential for tuning and optimizing performance. This precision-engineered part is ideal for enthusiasts building or restoring high-performance vehicles, including street machines and vintage hot rods.

Designed to work with Holley carburetors, the Primary Metering Block manages fuel flow through calibrated passages that ensure efficient atomization and combustion. Its compact design allows for easy integration into tight engine bays, while maintaining structural integrity and performance capabilities.

This metering block is best suited for Holley 4-barrel carburetor applications, supporting both small-block and big-block engines. Proper selection and setup of the metering block are crucial for achieving reliable performance in various automotive applications.