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COMP Cams GK11-601-8 Mutha' Thumpr 235/249 Hydraulic Roller Camshaft Gear Drive Kit

(Chevrolet Camaro 1967-72, Corvette 1967-74, Impala 1965-76, Malibu 1966-67, 1973-75, C1500 1990-93, Chevelle 1965-73, Blazer 1973-74 + 107 more models)

Manufacturer

Picture for manufacturer COMP Cams

Part Number

GK11-601-8
6 reviews
Sale Price

$1,529.95

Estimated ship date Tuesday, November 24

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Product Details

The COMP Cams GK11-601-8 Mutha' Thumpr Hydraulic Roller Camshaft Gear Drive Kit is engineered for Chevrolet Big Block 396-454 engines seeking aggressive street/strip performance with that iconic thumping idle sound. This complete GK-Kit includes the Mutha' Thumpr camshaft, hydraulic roller lifters, and a precision gear drive timing set for superior accuracy and durability.

Performance Specifications:

  • Grind Number: 291THR7
  • Advertised Duration: 291° Intake / 311° Exhaust
  • Duration at .050": 235° Intake / 249° Exhaust
  • Valve Lift: .558" Intake / .542" Exhaust
  • Lobe Separation: 107°
  • Operating RPM Range: 2,200-5,800 RPM
  • Camshaft Material: Austempered Ductile Iron
  • Camshaft Gear Attachment: 3-Bolt

What's Included:

  • Mutha' Thumpr Hydraulic Roller Camshaft
  • High-performance Hydraulic Roller Lifters
  • Precision-Machined Gear Drive Timing Set with Heat-Treated Billet Steel Gears
  • 3-Way Crank Sprocket with 4° Maximum Advance or Retard
  • Mounting Bolts and Lock Plates
  • Assembly Lube, Decals, and Detailed Installation Instructions

This Mutha' Thumpr grind delivers impressive horsepower and torque gains while producing a powerful, hard-hitting exhaust note with a rough idle. The unique lobe profile combines early exhaust valve opening with long exhaust duration and optimized valve overlap to create that signature muscle car sound without sacrificing power output or drivability.

Recommended Requirements: Best suited for high-performance street/strip applications with 9:1 minimum compression ratio, 2,500+ RPM stall converter, aftermarket intake, performance gears, and headers. Expect a rough, choppy idle characteristic of classic hot rod engines. The included gear drive provides exceptional timing accuracy and adds a distinctive mechanical whine for the ultimate vintage performance sound.

Designed specifically for 1967-1996 Chevrolet Big Block 396-454 cubic inch V8 engines in non-factory roller block applications. This is a retro-fit hydraulic roller design that works with both carbureted and fuel-injected engines.

Products specifications

Fits

Chevrolet Camaro 1967-72, Corvette 1967-74, Impala 1965-76, Malibu 1966-67, 1973-75, C1500 1990-93, Chevelle 1965-73, Blazer 1973-74, C10 Pickup 1968-74, Caprice 1966-76, C10 1975-81, El Camino 1966-75, Monte Carlo 1970-75 + 102 more models

Advertised Exhaust Duration

311

Advertised Intake Duration

291

Basic Operating RPM Range

2,200-5,800

Intake Valve Lift

0.558

Exhaust Valve Lift

0.542

Exhaust Duration at .050 inch Lift

249

Kit Type

GK-Kit - Cam and Gear Kit

AMAZON ASIN

B002EE73OG

Usage

Street/Performance

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

Locks Included

No

Lifter Type

Hydraulic Roller

Intake Duration at .050 Inch Lift

235

Cam Type

Hydraulic Roller

Lifters Included

Yes

Retainers Included

No

Timing Chain and Gears Included

Yes

Valve Stem Seals Included

No

Pushrods Included

No

Camshaft Series

Thumpr

Engine Family

Chevrolet 396-454 c.i. 8 Cylinder (1967-1996)

PLEASE HURRY SHIPPING THANKS--rgds, jdk

I ordered a set of inner tie rods for my car from Autoplicity and found their prices to be the lowest online for the brand I was looking for. Items were ship out in 2 business days from the original manufacturer. Shipping prices were kind of on the expensive end considering the package size and weight so if Autoplicity adjust their shipping prices to be more competitive, I think their service and pricing would be hard to beat!

Was disappointed that I paid for next day air shipping and it took 3 days to get my order. The part I received was good though. Just wish I wouldn't have lost out on all the extra shipping cost and had to make my customer wait an extra couple days.

Will the battery fit a 2000 inifinite i30

Order shipped quickly and Autoplicity had the best price. A pleasure to do business with. Thanks

Great selection of parts and great responses to orders through e mail

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