COMP Cams K31-601-9 - Mutha Thumpr 235/249 Hydraulic Roller & Evolution Lifter K-Kit, Ford 221-302

COMP Cams K31-601-9 - Mutha Thumpr 235/249 Hydraulic Roller & Evolution Lifter K-Kit, Ford 221-302

Mutha Thumpr 235/249 Hydraulic Roller & Evolution Lifter K-Kit, Ford 221-302

The COMP Cams Mutha Thumpr series delivers aggressive street/strip performance for Ford Small Block engines, producing a rough lopey idle, strong midrange power, and sharp throttle response. Ideal for 9:1 compression combos with headers.

The COMP Cams Xtreme Energy camshaft delivers enhanced street performance for Ford Small Block engines, providing very strong torque and horsepower gains with a smooth idle and responsive throttle—ideal for mild performance upgrades and heavier vehicle applications. Engineered for excellent low- to mid-range power, it works best with proven combinations such as the Edelbrock Performer intake manifold and a TCI Street Rodder or stock torque converter for reliable drivability. Featuring full-size base circles, this camshaft works seamlessly with COMP Cams Evolution hydraulic roller tappets and eliminates the need for dog bones and lifter retainers—components never intended for pre-1985 applications. This camshaft supersedes part number K31-601-8, delivering a dependable upgrade for improved performance and everyday usability.

• Features full-size base circles, works seamlessly with our Comp Cams Evolution hydraulic roller tappets.
• Eliminates the need for dog bones and lifter retainers, which were never intended for use in pre-1985 applications.
• Supersedes K31-601-8