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COMP Cams CL51-600-11 Thumpr 227/241 Hydraulic Roller Cam and Lifter Kit for Pontiac 265-455

Manufacturer

Picture for manufacturer COMP Cams

Part Number

CL51-600-11
5 reviews
Sale Price

$1,240.95

Estimated ship date Sunday, November 22

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Fitment guaranteed

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Product Details

The COMP Cams CL51-600-11 Thumpr Cam and Lifter Kit is engineered for Pontiac 265-455 cubic inch V8 engines and delivers the classic loping, aggressive idle that muscle car enthusiasts demand. Part of COMP Cams' popular Thumpr camshaft series, this kit is designed to produce a deep, choppy exhaust note while delivering strong street performance and impressive power gains.

The Thumpr grind features an intentionally asymmetric lobe design — with more duration on the exhaust side (241°) than the intake (227°) — which creates the signature uneven idle sound reminiscent of big-cube race engines, all while maintaining excellent streetability and vacuum for power brakes.

Camshaft Specifications:

  • Grind: Thumpr
  • Camshaft Style: Hydraulic Roller
  • Intake Duration (@ 0.050"): 227°
  • Exhaust Duration (@ 0.050"): 241°
  • Lobe Separation Angle: 107°
  • Application: Pontiac V8 265, 301, 326, 350, 389, 400, 421, 428, 455 cubic inch engines
  • Lifter Type: Hydraulic Roller

Kit Includes:

  • Thumpr Hydraulic Roller Camshaft
  • Matched Hydraulic Roller Lifters
  • Assembly Lube
  • COMP Cams Decals
  • Installation Instructions

This complete cam and lifter kit simplifies the installation process by providing matched components engineered to work together from the start. The hydraulic roller design reduces friction, improves throttle response, and eliminates the need for periodic valve lash adjustments, making it an ideal upgrade for street-driven Pontiac builds seeking both performance and that iconic American V8 sound.

Products specifications

Advertised Exhaust Duration

303

Basic Operating RPM Range

1,700-5,500

Grind Number

283THR7

Exhaust Valve Lift

0.498

Exhaust Duration at .050 inch Lift

241

K-Kit Upgrade

K51-600-11

Engine Family

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

Usage

Street/Performance

Assembly Lubricant Included

No

Camshaft Gear Attachment

1-Bolt

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.

Lifter Type

Hydraulic Roller

Intake Duration at .050 Inch Lift

227

Cam Type

Hydraulic Roller

Camshaft Material

Billet Steel

Intake Valve Lift

0.513

LOBE SEPARATION

107

Advertised Intake Duration

283

Camshaft Series

Thumpr

Best price/shipping match I found online!

Shopping, and Checkout, went very well, but let's hope by the time the package gets delivered it's still in one piece we'll see, I hope so.

Thank u so much exact match

First time customer. Super price, easy order, fast processing and delivery. Will definitely do more business in future.

Fast and easy transaction.

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