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COMP Cams CL51-602-5 Big Mutha' Thumpr 243/257 Hydraulic Flat Camshaft and Lifter Kit

Manufacturer

Picture for manufacturer COMP Cams

Part Number

CL51-602-5
4 reviews
Sale Price

$468.95

Estimated ship date Thursday, October 22

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Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The COMP Cams Big Mutha' Thumpr CL51-602-5 is a high-performance hydraulic flat tappet camshaft and lifter kit engineered specifically for Pontiac 265-455 cubic inch V8 engines. This cam delivers an aggressive 243/257 duration profile that produces the signature deep, lopey idle and massive torque characteristics that muscle car enthusiasts crave.

Key Features:

  • Hydraulic flat tappet design for reliable performance and easy maintenance
  • 243/257 advertised duration provides aggressive performance with streetable characteristics
  • Optimized for Pontiac 265, 301, 326, 350, 389, 400, 421, 428, and 455 engines
  • Produces signature Thumpr idle sound with strong mid-range and top-end power
  • Ideal for street rods, muscle cars, and weekend cruisers seeking maximum attitude

Complete Kit Includes:

  • Hydraulic flat tappet camshaft
  • Matched hydraulic lifter set (16 lifters)
  • Assembly lube for proper break-in
  • Installation instructions
  • COMP Cams decals

This complete kit ensures proper component matching and includes everything needed for cam installation except pushrods and timing set. The Big Mutha' Thumpr series is designed for enthusiasts who want maximum performance sound and street presence with reliable hydraulic operation. Best suited for engines with 9.0:1 or higher compression, aftermarket converters with 2,400+ stall, and performance exhaust systems.

Products specifications

Advertised Intake Duration

295

Basic Operating RPM Range

2,500-6,400

Cam Type

Hydraulic Flat Tappet

Kit Type

Cl-Kit - Cam and Lifter Kit

Exhaust Valve Lift

0.486

Intake Valve Lift

0.501

Intake Duration at .050 Inch Lift

243

Exhaust Duration at .050 inch Lift

257

Camshaft Material

Cast Iron

AMAZON ASIN

B005H89WEU

Engine Family

Pontiac 265-455 C.I. 8 Cylinder (1955-1981)

Assembly Lubricant Included

Yes

Camshaft Gear Attachment

1-Bolt

Valve Springs Required

Yes

Lifter Type

Hydraulic Flat Tappet

California Proposition 65

WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov

C.A.R.B. E.O. Number

N/A

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. Exemption Reason

N/A

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

Locks Included

No

Lifters Included

Yes

Retainers Included

No

Timing Chain and Gears Included

No

LOBE SEPARATION

107

Usage

Street/Strip

Advertised Exhaust Duration

313

Valve Stem Seals Included

No

Camshaft Series

Thumpr

Item in-stock and shipped fast. Will definitely buy again from seller.

Super fast shipping and the best price around. Can't beat that. Thanks.<br>Order#5981

Great business, fast shipping. I received the item in about 2-3 days.

Great seller, great prices!!

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