Comp Cams 127030 4.6L / 5.4L 3V Big Mutha Thumpr NSR Camshafts

These Comp Cams Big Mutha Thumpr Camshafts are about as rowdy as it gets for the 3V Engine. Extremely rough idle. Suggested for use with upgraded Intake Manifold and Ported Cylinder Heads. Excellent power gains from 4500 - 7000 RPM. 3.73 - 4.10 Gears and 3000 - 3400 Stall suggested. No Springs required, but they do require Comp Cams Phaser Limiter Kit.