Willy's Carburetor & Dyno Shop Carburetor Return Spring Kit

Willy's Carburetor & Dyno Shop Throttle Return Spring Kits

When a carburetor expert builds a return spring kit, every detail reflects decades of hands-on racing experience. Willy's Carburetor & Dyno Shop — founded in 1985 and widely recognized as "The Choice of Champions" across drag racing, circle track, dirt track, marine, and tractor pulling — brings that same race-proven philosophy to its carburetor return spring kits. These are not generic aftermarket parts; they are engineered by a team whose primary business is building and tuning high-performance carburetors every single day.

What Sets Willy's Return Spring Kits Apart

Throttle return springs are a critical safety and performance component. A weak, misrouted, or improperly tensioned spring can cause the throttle to hang open — a dangerous situation at any speed, let alone on a race track. Willy's addresses this with a thoughtfully designed kit that goes beyond simply replacing a spring.

• Dual primary throttle return springs: The kit features two throttle return springs on the primary throttle shaft, providing redundant closing force for maximum safety and consistent throttle response.
• Secondary shaft coverage: A dedicated third spring is included for the secondary throttle shaft, ensuring the entire throttle assembly snaps back reliably under all operating conditions.
• Air cleaner clearance relocation: All springs are repositioned for proper air cleaner clearance, eliminating interference issues that can plague standard spring placements on modified or race-style induction setups.
• Built-in adjustable throttle stop: The included steel bracket features a built-in adjustable throttle stop, giving tuners precise control over idle and wide-open throttle positioning without additional hardware.
• Gloss black powdercoat finish: The steel bracket is finished in a gloss black powdercoat for corrosion resistance and a clean, professional appearance under the hood.

Designed for Holley-Based Carburetors

Willy's return spring kits are designed specifically for Holley 4-barrel carburetors, the platform that forms the foundation of virtually all of Willy's own carburetor lineup. Whether you're running one of Willy's custom-built HP series carburetors or a standard Holley 4150-style unit, this kit integrates cleanly and functions as the factory throttle hardware should have from the start. The semi-universal fitment makes it a natural upgrade or replacement for a wide range of Holley-based performance applications.

The Right Finishing Touch for Any Carbureted Build

Because Willy's builds and dynos complete carburetor systems, their accessories — including this return spring kit — are designed to complement the full carburetor package rather than exist as an afterthought. For builders putting together a serious street or race engine, pairing a Willy's carburetor with a Willy's return spring kit means every component in the throttle system has been designed with the same performance priorities in mind. Browse the full Willy's Carburetor & Dyno Shop brand page or explore all carburetor return spring kits to find the right solution for your build.