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COMP Cams K51-601-11 Mutha' Thumpr 235/249 Hydraulic Roller Cam K-Kit for Pontiac 265-455

Manufacturer

Picture for manufacturer COMP Cams

Part Number

K51-601-11
7 reviews
Sale Price

$1,540.95

Estimated ship date Saturday, November 21

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Fitment guaranteed

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Product Details

The COMP Cams K51-601-11 Mutha' Thumpr Hydraulic Roller Cam K-Kit is a complete performance camshaft package designed for Pontiac 265-455 cubic inch engines. Built around COMP Cams' legendary Mutha' Thumpr grind, this kit delivers an aggressive, lopey idle with strong mid-range and top-end power — giving your Pontiac a true performance character both on the street and at the strip.

The Mutha' Thumpr series features an asymmetrical lobe separation design with 235° intake / 249° exhaust duration at 0.050", producing the signature loping idle sound enthusiasts love while maintaining excellent drivability. The hydraulic roller profile reduces valvetrain friction, extends component life, and eliminates the need for periodic valve lash adjustments.

K-Kit Includes Everything You Need:

  • Hydraulic Roller Camshaft — Mutha' Thumpr 235/249 grind
  • Hydraulic Roller Lifters — matched set for proper break-in and performance
  • Valve Springs — rated for the cam's lift and RPM range
  • Retainers — matched to the included springs
  • Valve Locks (Keepers) — for secure retainer retention
  • Valve Stem Seals — to prevent oil consumption and maintain clean combustion
  • Timing Chain Set — for precise cam timing and durability
  • Assembly Lube — ensures proper initial lubrication during startup
  • Decals and Instructions — for proper installation guidance

Purchasing a K-Kit eliminates the guesswork of component compatibility — every part is selected by COMP Cams' engineering team to work together as a complete, balanced valvetrain system. This is an ideal upgrade for street/strip Pontiac builds seeking serious power gains with a classic muscle car sound.

Products specifications

Advertised Exhaust Duration

311

Advertised Intake Duration

291

Basic Operating RPM Range

2,000-5,800

Grind Number

291THR7

Intake Valve Lift

0.522

Exhaust Valve Lift

0.508

Exhaust Duration at .050 inch Lift

249

Engine Family

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

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

235

Cam Type

Hydraulic Roller

Camshaft Material

Billet Steel

LOBE SEPARATION

107

Usage

Street/Strip

Camshaft Series

Thumpr

Great so far. Hopefully it will be a great process when I get the parts

Great prices great service!

all great

Was an absolute pleasure doing business with y'all! Looking forward to business in the future.

Great product

great

was quick

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