COMP Cams Camshaft CRB3 299Th R7 Thumper

If you're building a classic muscle car or street rod and want that unmistakable, aggressive idle that screams performance, the COMP Cams Big Mutha' Thumpr camshaft is a solid choice. This hydraulic roller camshaft is specifically designed for Chrysler B/RB 383, 400, 413, 426 Wedge, and 440 engines, fitting a wide range of vehicles from 1959 through 1978, including popular models like the Dodge Charger, Plymouth Barracuda, and Chrysler New Yorker. It's engineered to create significant horsepower gains and a broad torque curve, all while delivering that signature rough, race-car-like idle.

The Thumpr series camshafts achieve this unique sound and performance through an early intake valve opening and extended exhaust duration, which creates a lot of valve overlap. This overlap is what gives you that hard-hitting idle. To make sure your drivetrain can keep up with the engine's powerband, this camshaft typically requires an aftermarket torque converter with a stall speed of 2800 RPM or higher, a lower gear ratio in your rear end, and supporting modifications like an upgraded intake and headers. Because these cams reduce vacuum at idle, you'll also need a vacuum canister, pump, or hydroboost system if your vehicle relies on vacuum for power brakes.

This camshaft is intended for street/strip applications and works best with at least 9.5:1 compression. It's a well-built component designed to make your engine perform and sound like a true performance machine. Please note that this camshaft is not CARB approved and cannot be shipped to California. Always refer to the manufacturer's installation instructions for complete details on requirements and proper setup.