Order Status & Returns
Gift Cards
Help Center
1-800-345-4545
Vehicle Info NeededBig Mutha Thumpr Retro-Fit Hydraulic Roller Camshaft Complete Kit Lift: .532"/.519"
Ships on 10/20/2026
Lowest Price Guarantee- Big Mutha Thumpr Retro-Fit Hydraulic Roller Camshaft & Lifter Kit
- Lift:.532"/.519"
- Duration:299°/319°
- Lobe Separation Angle:107°
- RPM Range:2300-6100
Big Mutha' Thumpr™ 243/257 Hydraulic Roller Cam K Kit for Pontiac 265-455. Street/strip, needs 9.5:1 compression, 2800+ stall, intake, gears and headers, very rough idle.
Pontiac; Super Duty; SD; SD455; HO; 455 HO; Trans-Am; Catalina; Firebird; Formula; 421; 455; 400; 428; 350; 265; 301; 370; 389; 301; 287; 317; 347; Ram Air; Ram Air IV; Ram Air III; Bonneville; Grand Prix; LeMans; Parisienne; Grand Am; Century; Regal;
Emissions Note:
This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.
CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART
Peak Power & Reliability
The Thumpr line of camshafts is a series of retro-fit hydraulic roller camshafts designed for use in 1955- 1998 262-400 cubic inch Small Block Chevrolet engines equipped with flat tappet camshafts. Thumpr Camshafts possess such an aggressive exhaust note due to the lobe profiles and grind characteristics chosen by the COMP Cams engineers. These camshafts produce a combination of early exhaust valve opening, long exhaust duration, and a generous amount of intake and exhaust overlap to maximize the rough-idling characteristics. Their cutting-edge hydraulic roller design will deliver a substantial power increase over an identical hydraulic flat tappet grind without sacrificing reliability or ease of maintenance. So look no further than the Thumpr line of camshafts - engineered to deliver that much sought-after ''thumping'' idle quality to Small Block Chevy owners everywhere.
Show More
Camshaft & Lifter Kits are indicated by a CL in their part number and include Camshaft, Lifters, Assembly Lube, Decals, and Instructions.
Complete Kits are indicated by a K in their part number and include Camshaft, Lifters, Timing Chain & Gears, Valve Springs, Retainers, Locks, Assembly Lube, Decals, and Instructions.
Unlock serious performance and aggressive sound with the Comp Cams Thumpr Hydraulic Roller Cams—the perfect choice for muscle car enthusiasts and performance builders looking to make a statement. These cams are specifically designed to deliver increased horsepower and torque while providing that signature "thumpy" idle that turns heads at every stoplight.
Whether you're building a street machine or upgrading your engine for track days, the Thumpr cam gives your vehicle a noticeable boost in performance without compromising reliability. These cams feature a hydraulic roller design that offers superior durability, allowing for better valve control at higher RPMs, reducing friction, and increasing engine efficiency.
For those seeking an even more aggressive profile, the Mutha Thumpr cam offers an even more intense sound and performance upgrade. With optimized lobe profiles, this cam produces a lopey idle and delivers peak performance at mid to high RPM ranges, ensuring your engine performs at its best when you need it most.
Perfect for anyone looking to enhance the power, sound, and style of their ride, the Thumper cam is engineered for vehicles with modified cylinder heads, high-compression ratios, and other performance upgrades. Comp Cams delivers exceptional quality and precision, ensuring that these cams will stand the test of time.
Shop JEGS today to take your engine's performance and sound to the next level with Comp Cams Thumpr Hydraulic Roller Cams—designed for the enthusiast who wants more power and attitude.
