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Founder, 1929-2014
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Holley 37-474 2 Barrel 500 CFM Rebuild Kit

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Holley 37-474 2 Barrel 500 CFM Rebuild Kit

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Q & A

What's in the Box

Each Holley Renew Kit carburetor rebuild kit contains all parts and gaskets that are necessary to restore “like new” performance to your carburetor. Detailed instructions are also included to guide you through the rebuilding process. Start off the season with a quality Holley Renew Kit repair kit. It's your guarantee for trouble–free cruising.

Fits Holley Model 2300 500cfm two barrel carburetors ONLY.

  • Gaskets
  • O-Rings
  • Pump Diaphragm
  • Needle & Seat
  • Power Valve
  • Instructions

427-37474 Instruction Sheet (PDF)


This rebuild kit will service the following Holley Carburetors

R4412     R4412-1   R4412-2   R4412-3   R9011     R84412

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Speedway Illustration

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427-371543 Instructions (PDF)

Wehrs Machine WM47 Carburetor Feet
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