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COMP Cams CL12-601-4 Mutha' Thumpr 235/249 Hydraulic Flat Cam and Lifter Kit for Chevrolet 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

CL12-601-4
8 reviews
Sale Price

$397.95

In Stock (10+)

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Usually delivered within 2 days

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Product Details

The COMP Cams Mutha' Thumpr CL12-601-4 is a complete hydraulic flat tappet camshaft and lifter kit engineered specifically for Chevrolet small block engines. This aggressive cam delivers the iconic Thumpr sound with excellent street performance and a powerful lopey idle that announces your engine's presence.

Camshaft Specifications:

  • Advertised Duration: 235°/249° (Intake/Exhaust)
  • Duration at .050": 207°/221°
  • Valve Lift: .474"/.486" (with 1.5 rocker ratio)
  • Lobe Separation Angle: 112°
  • Hydraulic flat tappet design for reliable street performance

Complete Kit Includes:

  • Camshaft engineered for Chevrolet Small Block engines
  • Hydraulic flat tappet lifters (16 pieces)
  • Assembly lube for proper break-in
  • Installation instructions
  • COMP Cams decals

Performance Characteristics:

  • Recommended RPM Range: 1,600-5,600 RPM
  • Produces aggressive lope idle and strong mid-range torque
  • Ideal for street performance applications with automatic or manual transmissions
  • Works with stock torque converters (2,000-2,400 stall recommended for best results)
  • Compatible with stock or aftermarket cylinder heads

The Mutha' Thumpr series is designed for enthusiasts who want maximum sound and performance on the street. This cam provides noticeably improved throttle response and power delivery throughout the RPM range while maintaining street-friendly manners. Requires compatible valve springs and proper break-in procedure for optimal performance and longevity.

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

305

Basic Operating RPM Range

2,200-6,100

Cam Type

Hydraulic Flat Tappet

Kit Type

Cl-Kit - Cam and Lifter Kit

Exhaust Valve Lift

0.476

Intake Valve Lift

0.489

Exhaust Duration at .050 inch Lift

249

Camshaft Material

Cast Iron

SK-Kit Upgrade

GK12-601-4

K-Kit Upgrade

K12-601-4

AMAZON ASIN

B002EE2ZDK

Assembly Lubricant Included

Yes

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.

Gaskets Included

No

Camshaft Gear Attachment

3-Bolt

Locks Included

No

Intake Duration at .050 Inch Lift

235

Lifters Included

Yes

Retainers Included

No

Timing Chain and Gears Included

No

LOBE SEPARATION

107

Usage

Street/Strip

Advertised Intake Duration

287

Engine Family

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

Valve Stem Seals Included

No

Camshaft Series

Thumpr

Best price around! I can't believe the deal I got on my part for my Jeep Cherokee. Just waiting now for it to arrive in the mail.

Great to order from shipping was fast and just awesome service will order from here again

Very speedy and in excellent shape. Easy to install and only took minutes. Autoplicity in my book is a great place to shop. <br><br>-Jason Chance<br> Cape Fair, MO

Great prices and fast delivery. I ordered my cam+springs+phaser kit for my 2007 mustang, I found the best prices with Autoplicity. Strongly recommend and most certainly purchasing here again

Ordered Lucas gear oil and have to say the service is great and delivery was very quick. I will recommend Autoplicity for quality yet affordable prices. will do business with again!

Great customer service. Quick and fast service. Great product knowledge

My first order and I must say, very impressive! Awesome prices and super-fast shipping direct from the manufacturer. Couldn't ask for more! I will return.

Excellent price on name brand items, best prices for Bosch oxygen sensors.

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