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COMP Cams 08-602-8 Big Mutha' Thumpr Hydraulic Roller Camshaft 243/257 SBC

(GMC G2500 1987-95, Yukon 1992-95, K1500 1988-95, C1500 1988-95, K2500 1988-95, Jimmy 1987-91, C3500 1988-95, K2500 Suburban 1992-95 + 89 more models)

Manufacturer

Picture for manufacturer COMP Cams

Part Number

08-602-8
5 reviews
Sale Price

$577.95

In Stock (8)

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Usually delivered within 2 days

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Product Details

The COMP Cams Big Mutha' Thumpr camshaft delivers an aggressive idle and strong mid-range performance for small block Chevy engines equipped with factory roller lifters. This hydraulic roller cam features 243° intake and 257° exhaust duration (advertised), creating the distinctive lope that muscle car enthusiasts crave while maintaining excellent drivability.

Key Specifications:

  • Intake Duration: 243° advertised / 191° @ .050"
  • Exhaust Duration: 257° advertised / 199° @ .050"
  • Valve Lift: .525" intake / .525" exhaust (with 1.5 rocker ratio)
  • Lobe Separation Angle: 112°
  • Hydraulic roller design for OE roller blocks
  • RPM Range: 1,800-5,400

Features & Benefits:

  • Pronounced aggressive idle tone with excellent vacuum characteristics
  • Optimized for street/strip applications with automatic or manual transmissions
  • Works with factory fuel injection and compression ratios of 9.0:1 or higher
  • Compatible with OE hydraulic roller lifters and factory valve springs in most applications
  • Designed for engines ranging from 262ci to 400ci

The Big Mutha' Thumpr series offers enthusiasts a significant step up from the standard Thumpr profile, delivering more aggressive sound and stronger performance while remaining streetable. This camshaft requires proper valve spring verification and may require computer recalibration on fuel-injected applications.

Products specifications

Fits

GMC G2500 1987-95, Yukon 1992-95, K1500 1988-95, C1500 1988-95, K2500 1988-95, Jimmy 1987-91, C3500 1988-95, K2500 Suburban 1992-95, K3500 1988-95, C2500 1988-95, K1500 Suburban 1992-95, G25/G2500 Van 1987-95, C1500 Suburban 1992-95 + 84 more models

Advertised Exhaust Duration

319

Advertised Intake Duration

299

Basic Operating RPM Range

1,900-5,600

Grind Number

299THR7

Engine Family

Chevrolet 305-350 c.i. 8 Cylinder O.E. Roller (1987-1998)

Exhaust Valve Lift

0.519

Intake Valve Lift

0.533

Intake Duration at .050 Inch Lift

243

Exhaust Duration at .050 inch Lift

257

Camshaft Material

Austempered Ductile Iron

Cam and Lifter Kit Upgrade

CL08-602-8

K-Kit Upgrade

K08-602-8

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

LOBE SEPARATION

107

Usage

Street/Strip

AMAZON ASIN

B002EDWNQ0

Cam, Lifter and Gear Drive Upgrade

GK08-602-8

Camshaft Series

Thumpr

Great Price on products and Shipping

Fast shipping, Good communication, Highly recommended.!!!

quick delivery of the parts I need to fix my jeep

It was good

The whole process was some and quick. They also had the lowest prices available. Will be using them more often for sure!!

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