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
- Standard Emulsion Jet
- 0.078 in. Jet Size
- 6/32 Thread
- 2 Per Package
- Sizes From 00-78
Holley Performance Emission Code 5: This part is legal for sale or use on Emissions Controlled Vehicles; Uncontrolled (Non-Emissions Controlled) Vehicles; and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations
Fits All Holley Ultra XP™ & Doninator® Billet Metering Blocks. Holley does not recommend changing emulsion jets unless you are a competent carburetor tuner and have the correct test equipment to record the changes.
About Holley Performance Products
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors powered every Monster Energy NASCAR Cup team and nearly every NHRA Pro-Stock champion for four decades. Now, Holley EFI products power these cars and are dominating the performance world. Holley products for GM's popular LS engine are dominating the LS scene as well. Holley's products also include performance fuel pumps, intake manifolds and engine dress-up products for street performance, race and marine applications. As a single solution or partnered with products from other Holley companies we can give you the edge you need over the competition!
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Holley Carburetor Jet 142-78: