4150/4160 Fast Idle Cam

The Holley 4150/4160 Fast Idle Cam is a vital replacement component designed specifically for Holley 4150 and 4160 series carburetors, ensuring precise idle speed control during cold starts and warm-up cycles. This part is essential for mechanics and enthusiasts who are rebuilding or servicing classic carburetors.

The fast-idle cam functions through a temperature-sensitive linkage that adjusts the carburetor's throttle blade as the engine warms up. As the coolant temperature rises, the cam gradually returns to its idle position, lowering RPM and leaning the air-fuel mixture until the engine stabilizes at normal idle. Its compact and durable design ensures smooth transitions without binding or hesitation.

This replacement cam is ideal for restoring drivability in vehicles equipped with Holley 4150 or 4160 carburetors, including street-driven classics and vintage race engines that require reliable cold-start performance.