These metering orifices control fuel flow into the metering system. They are rated in flow capacity "cubic centimeters per minute" and are changeable for tuning purposes. The shape of the entry, exit, and size determines flow. All Holley Main jets are flow tested and then stamped with the correct number.

• Fits All Holley Model 2010, 2300, 4010, 4011, 4150, 4160 & 4500
• Sizes from 40-110
• 1/4-32 Thread
• .081" Jet size
• Standard Main Jet
• Jet Hole sizes provided for reference only . All Holley jets are sized by actual flow and may vary from sizes above.