Mutha" Thumpr Hydraulic Flat Tappet Camshaft Pro-Plasma Nitrided Lift .498"/.483" Duration 279/297 RPM Range 1800 to 5600
InfoVehicle Info Needed
COMP CAMSPART NUMBER: 249-12-601-20

Mutha" Thumpr Hydraulic Flat Tappet Camshaft Pro-Plasma Nitrided Lift .498"/.483" Duration 279/297 RPM Range 1800 to 5600

$46895
ShippingShips on 09/15/2026
Lowest PriceLowest Price Guarantee

Chevy 262-400ci Small Block 1958-98
    Mutha' Thumpr Hydraulic Flat Tappet Camshaft
    Pro-Plasma Nitrided
    Lift .498"/.483"
    Duration 279/297
    RPM Range 1800 to 5600

    Nitrided

    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/strip, needs 9:1 compression, 2500+ stall, intake, gears and headers, rough idle. Nitrided.

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

Thumpr Camshafts are the hottest cams to hit the streets in more than a decade. That's because they give you the big cam sound you're looking for, without the drawbacks. Applying a camshaft design originally created for sports car endurance racing, they incorporate early exhaust valve opening, long exhaust duration, and a generous amount of intake and exhaust overlap. Best of all, Thumprs will not negatively impact power output or streetability.

Show More Features:
  • Three unique cam designs for each application that deliver excellent horsepower gains and broad torque curve; perfect choice for muscle cars and street rods
  • Early intake valve opening and long exhaust duration create optimum overlap for powerful, hard-hitting exhaust note
  • Best with aftermarket converters and more rear gear

    Thumpr Sound ClipClick to Listen

    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.

The Comp Cams Thumpr Hydraulic Flat Tappet Cams are the perfect solution for muscle car enthusiasts and performance builders seeking that aggressive "thumpy" idle and increased engine power. Engineered to deliver impressive performance without sacrificing drivability, these camshafts are designed for vehicles that demand high-performance upgrades. Whether you're building a street rod, classic muscle car, or high-performance engine, the Thumpr camshaft is the ideal choice for anyone looking to take their ride to the next level.

The Big Mutha Thumpr cam kit is tailored for those looking for a more aggressive, lopey idle while boosting horsepower and torque. These camshafts are specifically designed to provide maximum power and enhanced throttle response, particularly at mid-range RPMs, making them a top choice for street performance builds.

The performance camshaft offers an ideal balance between street-friendly drivability and high-performance capability. With a unique lobe design, the Thumpr camshaft provides an unmistakable sound while increasing airflow and valve timing for more robust power delivery. These camshafts are perfect for enthusiasts who want to enhance both the sound and performance of their engine.

If you're seeking a camshaft that makes your engine roar with authority while delivering tangible performance gains, look no further than the Comp Cams Thumpr Hydraulic Flat Tappet Cams. Upgrade your engine today and experience the difference in power, performance, and sound!

Part TypeCamshaft
Product LineComp Cams Thumpr Hydraulic Flat Tappet Cams
BrandCOMP CAMS
Package Height2.75
Package Width3.0
Package Length24.5
Weight8.64 PG
Part CategoryPerformance Parts
Exh. Duration @ .050 In. (Deg)249
Cam StyleHydraulic flat tappet
Grind Number287TH7
Exh. Duration Advertised (Deg)305
Engine Make/SizeChevy Small Block (262-400)
Intake Valve Lift With Factory Rocker Arm Ratio (I0.489
Int. Duration @ .050 In. (Deg)235
Basic Operating Rpm Range2,200-6,100
Intake Valve Lift0.489 in (12.421 mm)
Computer-Controlled CompatibleNo
Int. Duration Advertised (Deg)287
Lobe Separation (Deg)107
Rpm Range2200-6100
Advertised Duration287 int./305 exh.
Exhaust Valve Lift With Factory Rocker Arm Ratio (0.476
UsageStreet/Strip
Valve Lift With Factory Rocker Arm Ratio0.489 int./0.476 exh.
Camshaft Gear Attachment3-bolt
QuantitySold individually
Exhaust Valve Lift0.476 in (12.09 mm)
Advertised Intake Duration287
Intake Duration At 050 Inch Lift235
Exhaust Duration At 050 Inch Lift249
Advertised Exhaust Duration305
Lifter TypeHydraulic Flat Tappet
Duration At 050 Inch Lift235 int./249 exh.
Valve Springs RequiredYes
Vendor Part Number12-601-20
Package Qty1
Package TypeEA
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Some parts are not legal for use in California or other states with similar laws / regulations
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