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COMP Cams 42-601-11 Mutha' Thumpr 235/249 Hydraulic Roller Camshaft for Oldsmobile 260-455

Manufacturer

Picture for manufacturer COMP Cams

Part Number

42-601-11
14 reviews
Sale Price

$608.95

2 left at this price

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Product Details

The COMP Cams 42-601-11 Mutha' Thumpr is a retro-fit hydraulic roller camshaft engineered for high performance street/strip Oldsmobile 260-455 V8 engines. Designed to deliver a powerful, hard-hitting exhaust note with a distinctly rough idle, this cam grind sits in the middle of COMP's Thumpr lineup — offering more duration and overlap than the standard Thumpr while remaining streetable for performance builds.

COMP Cams developed the Thumpr family of cam grinds to combine that classic aggressive idle sound with real-world horsepower and torque gains. The Mutha' Thumpr grind uses early intake valve opening and extended exhaust duration to create optimum overlap, producing a broad torque curve and impressive top-end power. This hydraulic roller design eliminates the maintenance associated with flat tappet or solid roller cams while still delivering serious performance.

Camshaft Specifications:

  • Lifter Type: Hydraulic Roller
  • Duration @ .050" Lift: 235° Intake / 249° Exhaust
  • Advertised Duration: 291° Intake / 311° Exhaust
  • Valve Lift: 0.540" Intake / 0.532" Exhaust
  • Lobe Separation Angle: 107°
  • RPM Operating Range: 2,200 – 5,900
  • Grind Number: 291THR7

Recommended Build Requirements:

  • Minimum 9:1 compression ratio
  • 2,500+ RPM stall speed converter recommended
  • Performance intake manifold required
  • Numerically higher rear axle gears recommended
  • Headers strongly recommended
  • Expect a rough, lopey idle character

Engine Compatibility: Designed for 1967 and later Oldsmobile 260, 307, 350, 400, 403, 425, and 455 cubic inch V8 engines. This camshaft is sold individually. For a complete cam and lifter kit, see COMP Cams part number CL42-601-11.

Products specifications

Advertised Exhaust Duration

311

Advertised Intake Duration

291

Basic Operating RPM Range

2,000-5,800

Grind Number

291THR7

Intake Valve Lift

0.54

Exhaust Valve Lift

0.532

Exhaust Duration at .050 inch Lift

249

Cam and Lifter Kit Upgrade

CL42-601-11

K-Kit Upgrade

K42-601-11

Engine Family

Oldsmobile 260-455 c.i. 8 Cylinder (1967-1990)

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

good price

Good to shop with.

Having Paypal checkout made me decide to order. Appreciate knowing your quantity on hand too. Very glad you had my part.

Thank you for having the items needed

As long as this fits my 2015 Evo X ill be happy.

The order process was easy. I they ship out right away.

love it

Pretty good not great for a mobile phone but youcan get around the inconveniences

Great

Thanks

Autoplicity was easy to deal with, and the price was hard to beat. Will use again.

Best price around, very fast shipping and great service! I will buy from them again!

Simple

quick turn around great price

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