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Beginner — under 30 min
Overview
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Part #: 122-5000
An improved jet extension design that actually screws into the metering block. The main metering jet then threads into the end of the extension. The installation effectively moves the fuel entry point for the main jet out into the fuel bowl. In this location it cannot be uncovered by fuel, causing a lean condition, during periods of hard acceleration or braking. 2/Pkg.
Features:
- Improved Design
- 2 Per Package
Main Jet Extension
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Specifications
| Brand | Holley |
| Part Number | H00E 122-5000 |
| Weight | 0.04 lb |
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Returns & Fitment
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.
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