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COMP Cams 12-602-8 Big Mutha' Thumpr Hydraulic Roller Camshaft for Chevy Small Block

(GMC G2500 1979-95, Yukon 1992-95, K1500 1979-86, 1988-95, C1500 1979-86, 1988-95, K2500 1979-86, 1988-95, Jimmy 1970-91 + 242 more models)

Manufacturer

Picture for manufacturer COMP Cams

Part Number

12-602-8
5 reviews
Sale Price

$577.95

In Stock (10+)

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Usually delivered within 2 days

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Product Details

The COMP Cams Big Mutha' Thumpr camshaft is designed for serious street performance enthusiasts who want aggressive sound and impressive torque from their Chevrolet small block engine. This hydraulic roller camshaft features 243/257 degrees of advertised duration, delivering the distinctive lope at idle that made the Thumpr series famous, while providing strong mid-range power for street and strip applications.

Key Specifications:

  • Advertised Duration: 243°/257° (Intake/Exhaust)
  • Duration @ .050": 212°/220°
  • Valve Lift: .474"/.501" (with 1.5 rocker ratio)
  • Lobe Separation Angle: 112°
  • Hydraulic roller design for reduced friction and wear
  • Compatible with factory or aftermarket fuel injection

Performance Features:

  • Aggressive lopey idle that announces serious performance
  • Optimized for engines with 9.0:1 to 10.5:1 compression ratio
  • Power range: 1,800-5,800 RPM
  • Works with stock torque converters and rear gears
  • Excellent choice for street rods, muscle cars, and daily drivers seeking that classic hot rod sound

This camshaft requires compatible hydraulic roller lifters, timing set, and valve springs (sold separately). The Big Mutha' Thumpr delivers maximum attitude with strong street performance, making it ideal for GM small blocks in applications ranging from classic Camaros and Chevelles to modern street machines.

Products specifications

Fits

GMC G2500 1979-95, Yukon 1992-95, K1500 1979-86, 1988-95, C1500 1979-86, 1988-95, K2500 1979-86, 1988-95, Jimmy 1970-91, C3500 1979-86, 1988-95, K2500 Suburban 1979-86, 1992-95, K3500 1979-86, 1988-95 + 239 more models

Advertised Exhaust Duration

319

Advertised Intake Duration

299

Basic Operating RPM Range

2,500-6,200

Grind Number

299THR7

Exhaust Valve Lift

0.517

Intake Valve Lift

0.531

Intake Duration at .050 Inch Lift

243

Exhaust Duration at .050 inch Lift

257

Camshaft Material

Austempered Ductile Iron

Cam and Lifter Kit Upgrade

CL12-602-8

K-Kit Upgrade

K12-602-8

Assembly Lubricant Included

No

Lifters Included

No

Valve Springs Required

Yes

Prop 65

WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov

C.A.R.B. Exempt for Foreign Vehicles Manufactured Before 1967?

Yes, but must meet tailpipe emission standards for year of vehicle.

C.A.R.B. Exempt for On-Road Vehicles?

No

C.A.R.B. Exempt for Racing and Off-Road Only Vehicles?

Yes, but must be a race/competition only vehicle.

C.A.R.B. Exempt for California Certified Vehicles Manufactured Before 1965?

Yes, but must meet tailpipe emission standards for year of vehicle.

C.A.R.B. Exempt for Federally Certified Vehicles Manufactured Before 1967?

Yes, but must meet tailpipe emission standards for year of vehicle.

Camshaft Gear Attachment

3-Bolt

Lifter Type

Hydraulic Roller

Cam Type

Hydraulic Roller

AMAZON ASIN

B000V9GBUS

LOBE SEPARATION

107

Usage

Street/Strip

Cam, Lifter and Gear Drive Upgrade

GK12-602-8

Engine Family

Chevrolet 262-400 c.i. 8 Cylinder (1958-1998)

Camshaft Series

Thumpr

The fellas at Autoplicity where great, very proffesional, and great price as well. I will definately be using them again. ohh, and super fast shipping... thank autoplicity...

Unbeliveable customer service and super fast shipping. I had a question about my order and I was able to use the online chat function to instantly connect with a customer service agent that was quick to answer all my questions regarding my order. I am very pleased with the level of service I received not to mention the great price they offered on the item I purchased. I will be sure to continue doing business with Autoplicity for my automotive needs. Thanks so much. A+

Good product, fast shipping, ease of shopping.

Enjoyed my time shopping

best price i could find online. fast shipping

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