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COMP Cams 12-602-20 Big Mutha' Thumpr Hydraulic Flat Camshaft for Chevy Small Block

(GMC G2500 1979-95, Yukon 1992-95, K1500 1979-99, C1500 1979-99, K2500 1979-95, 1998, Jimmy 1970-91, Savana 2500 1996-2002 + 259 more models)

Manufacturer

Picture for manufacturer COMP Cams

Part Number

12-602-20
7 reviews
Sale Price

$468.95

1 left at this price

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Product Details

The COMP Cams Big Mutha' Thumpr camshaft is engineered to deliver an aggressive, race-inspired exhaust note with substantial performance gains for Chevrolet small block engines. Featuring 243° intake duration and 257° exhaust duration, this hydraulic flat tappet camshaft produces the signature loping idle that enthusiasts crave while delivering excellent horsepower and a broad, usable torque curve.

Key Features:

  • Hydraulic flat tappet design for Chevrolet small block engines
  • 243° intake / 257° exhaust duration for aggressive sound and performance
  • Early intake valve opening and extended exhaust duration create optimal overlap
  • Delivers race car idle with hard-hitting exhaust note
  • Broad torque curve with excellent horsepower gains
  • Ideal for muscle cars, street rods, and performance street applications

Installation Requirements:

  • Aftermarket torque converter required for automatic transmissions
  • Lower gear ratio recommended to keep engine in powerband
  • Reduced idle vacuum requires vacuum canister, pump, or hydroboost for power brake systems
  • Not recommended for stock converters or high gear ratios

The Big Mutha' Thumpr is perfect for builders seeking maximum idle impact and strong street performance in their small block Chevy build. This camshaft is designed for those who want their vehicle to sound as aggressive as it performs.

Products specifications

Fits

GMC G2500 1979-95, Yukon 1992-95, K1500 1979-99, C1500 1979-99, K2500 1979-95, 1998, Jimmy 1970-91, Savana 2500 1996-2002, Savana 1500 1996-2002, C3500 1979-95, K2500 Suburban 1979-95, K3500 1979-95 + 255 more models

Advertised Intake Duration

295

Basic Operating RPM Range

2,500-6,400

Grind Number

295TH7

Cam Type

Hydraulic Flat Tappet

Exhaust Valve Lift

0.486

Intake Duration at .050 Inch Lift

243

Exhaust Duration at .050 inch Lift

257

Camshaft Material

Nitrided Cast Iron

Assembly Lubricant Included

Yes

Lifters Included

No

Valve Springs Required

Yes

Lifter Type

Hydraulic Flat Tappet

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

Intake Valve Lift

0.5

LOBE SEPARATION

107

Usage

Street/Strip

AMAZON ASIN

B002EE48VM

Advertised Exhaust Duration

313

Engine Family

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

Camshaft Series

Thumpr

First off, I LOVE my new shipments! These guys had everything at super low prices, and the shipping was phenomenally fast. It's all working great, and imm definitely buying from these guys again.

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I bought a Motive pressure brake bleeder from Autoplicity. I have been looking around for different prices for quite a while, and their price, even with shipping cost, was the lowest. After ordering, I received a notification of shipment and tracking number. The item arrived well packaged, complete, and intact within a few days. I am looking forward to using it.

Cheap prices, great quality, and fast delivery. Autoplicity will continue to receive my patronage.

Easy and fast. Order arrived very fast. Thanks.

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