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EC Adjustable Gas Main Jet Kit  for Stock Carburetor on Honda GX390 & Big Block Clones
169F-43G390 EC Adjustable Needle Gas Kit for GX390 Clone Ruxing Carb
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EC Adjustable Gas Main Jet Kit for Stock Carburetor on Honda GX390 & Big Block Clones

Part Number: 169F-43G390
Online Price: $21.99
Adjustable Gas Main Jet Kit – Fits Stock Carburetors on GX390 & Big Block Clones
Availability: In Stock.

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Description

EC Adjustable Main Jet Kit – Fits Stock Carburetor on Honda GX390 / Predator 420 / Big Block Clones


Take full control of your fuel tuning with EC’s new Adjustable Main Jet, designed specifically for the stock carburetor found on Honda GX390-style Big Block Clone engines, including Predator 420 and Wildcat 460.


Say goodbye to the hassle of swapping out individual jets or disassembling your carburetor every time the weather changes. This precision-designed kit replaces 10+ traditional jet sizes, giving you on-the-fly adjustability with just a turn of the needle. Whether you're compensating for changes in altitude, humidity, fuel type, or temperature, this adjustable jet makes fine-tuning simple, fast, and repeatable.


Key Features:

  • Full-range tunability without removing the carburetor or bowl
  • Brass needle and nut provide precise alignment and stable fuel delivery
  • Compact design for improved fitment and wheel clearance
  • Replaces over 10 standard main jets
  • Ideal for dialing in performance in racing or variable climate conditions
  • Designed for use with gasoline only (not methanol-compatible)


What's Included in the Kit:

  • Adjustable Brass Needle
  • Main Jet
  • Bowl Washer Gasket
  • Low-Speed/Pilot Jet


Compatibility:

  • Honda GX390 Stock Carburetor
  • Predator 420
  • Wildcat 460
  • Other GX390-style clone engines with stock-style carburetors

Note: This kit is configured for gasoline use. For methanol setups, use a compatible adjustable jet kit designed for alcohol-based fuels.

FAQ

Q1: What does the adjustable main jet do?
A: The adjustable main jet replaces multiple fixed-size jets, allowing you to fine-tune your fuel mixture by simply turning a needle—no need to remove the carburetor or bowl.


Q2: What engines is this compatible with?
A: This kit fits stock carburetors found on most Honda GX390, Predator 420, Wildcat 460, and other GX390-style big block clone engines.


Q3: Is this kit compatible with methanol fuel?
A: No. This version is specifically designed for gasoline use only. A methanol-compatible version would require different flow and needle sizing.


Q4: How many jets does this replace?
A: The adjustable needle provides a range that effectively replaces 10 or more standard jet sizes, offering easy tuning for changes in temperature, elevation, humidity, and fuel.


Q5: Does this kit work on modified engines?
A: Yes, it's especially useful for performance or race engines that need fine-tuning across various track or environmental conditions—without needing to re-jet every time.


Q6: What comes in the kit?
A: Each kit includes:

  • Adjustable brass needle
  • Main jet
  • Bowl washer gasket
  • Pilot/low-speed jet

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