Thumpr Retro-Fit Hydraulic Roller Camshaft Lift: .513"/.498"
InfoVehicle Info Needed
COMP CAMSPART NUMBER: 249-12-600-8

Thumpr Retro-Fit Hydraulic Roller Camshaft Lift: .513"/.498"

$54995
ShippingShips on Oct 02, 2026
Lowest PriceLowest Price Guarantee

Chevy 262-400ci Small Block 1958-98 Non-Factory Roller Block
  • Thumpr
    • Thumpr Retro-Fit Hydraulic Roller Camshaft
    • Lift: .513"/.498"
    • Duration: 283°/303°
    • Lobe Separation Angle: 107°
    • RPM Range: 1900-5600

    • 3 Grinds To Fit All Of Your Performance Needs
    • Long Exhaust Duration
    • Produces A Powerful Hard-Hitting Exhaust Note
    • Excellent Horsepower Gains And Broad Torque Curve
    • Delivers Real Seat Of The Pants Performance
    • Designed For Use w/Latest In ValveTrain Components
    • 1 Year Limited Warranty

      265, 283, 307, 302, 305, 327, 350, 383, 400, 427, L46, L48, L65, LM1, LT-1, L82, L81, LS9, L83, L98, L05, LG3, LG4, LT1, LT4, Camaro, Corvette, Chevelle, Stingray, Silverado, C10, Firebird, Chevrolet, Chevy, Small Block Chevy, Caprice, Malibu, Impala, Nova, 355, GEN1, Monte Carlo, S10


      High performance street, stock converter ok, best with 2000+ converter and gears, choppy/thumping idle.

    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.

    Part TypeCamshaft
    Product LineComp Cams Thumpr Hydraulic Roller Cams
    BrandCOMP CAMS
    Package Height2.8
    Package Width2.9
    Package Length24.3
    Weight8.9 PG
    Part CategoryPerformance Parts
    Exh. Duration @ .050 In. (Deg)241
    Cam StyleHydraulic roller tappet
    Grind Number283THR7
    Exh. Duration Advertised (Deg)303
    Engine Make/SizeChevy Small Block (262-400)
    Intake Valve Lift With Factory Rocker Arm Ratio (I0.511
    Int. Duration @ .050 In. (Deg)227
    Basic Operating Rpm Range1,900-5,600
    Intake Valve Lift0.511 in (12.979 mm)
    Computer-Controlled CompatibleNo
    Int. Duration Advertised (Deg)283
    Lobe Separation (Deg)107
    Rpm Range1900-5600
    Advertised Duration283 int./303 exh.
    Exhaust Valve Lift With Factory Rocker Arm Ratio (0.497
    UsageStreet/Performance
    Valve Lift With Factory Rocker Arm Ratio0.511 int./0.497 exh.
    QuantitySold individually
    Exhaust Valve Lift0.497 in (12.624 mm)
    Advertised Intake Duration283
    Intake Duration At 050 Inch Lift227
    Exhaust Duration At 050 Inch Lift241
    Advertised Exhaust Duration303
    Lifter TypeHydraulic Roller Retrofit
    Part FitmentSemi Universal
    Duration At 050 Inch Lift227 int./241 exh.
    Valve Springs RequiredYes
    Vendor Part Number12-600-8
    Package Qty1
    Package TypeEA
    No Questions
    No Reviews

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