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COMP Cams K31-603-5 Big Mutha' Thumpr Hydraulic Flat Cam K-Kit for Ford Engine Camshaft Kit - 221-302

(Ford Mustang 1964-95, Thunderbird 1977-81, 1983-88, 1991-93, Maverick 1971-77, Galaxie 500 1963-72, Fairlane 1963-70, Torino 1968-74 + 40 more models)

Manufacturer

Picture for manufacturer COMP Cams

Part Number

K31-603-5
5 reviews
Sale Price

$730.95

1 left at this price

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Usually delivered within 2 days

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Product Details

The COMP Cams Big Mutha' Thumpr K31-603-5 is a complete camshaft kit engineered for Ford small block 221-302 cubic inch engines. This aggressive hydraulic flat tappet camshaft delivers a distinctive lopey idle and powerful mid-range performance, making it ideal for street/strip applications and hot rods where a radical sound and strong torque are desired.

Camshaft Specifications:

  • Advertised Duration: 243°/257° (Intake/Exhaust)
  • Hydraulic flat tappet design for reliable street performance
  • Aggressive lobe profile for maximum throttle response
  • Optimized for carbureted applications

Complete K-Kit Includes:

  • Camshaft with precision-ground lobes
  • Hydraulic flat tappet lifters (16)
  • High-performance valve springs
  • Steel valve spring retainers
  • Valve locks (keepers)
  • Valve stem seals
  • Timing chain set with gears
  • Assembly lube for proper break-in
  • Installation instructions and decals

This all-in-one kit provides everything needed for a professional camshaft installation, eliminating the guesswork of component matching. The Big Mutha' Thumpr series is designed for enthusiasts who want aggressive sound and performance without sacrificing streetability. Recommended for engines with aftermarket intake manifolds, headers, and lower gear ratios to maximize performance potential.

Products specifications

Fits

Ford Mustang 1964-95, Thunderbird 1977-81, 1983-88, 1991-93, Maverick 1971-77, Galaxie 500 1963-72, Fairlane 1963-70, Torino 1968-74, Mustang II 1975-78, Falcon 1964-70, Galaxie 1963-67, Gran Torino 1972-74, LTD 1965-86 + 35 more models

Advertised Exhaust Duration

312

Advertised Intake Duration

295

Basic Operating RPM Range

2,500-6,400

Cam Type

Hydraulic Flat Tappet

Engine Family

Ford 221, 260, 289, 302 c.i. 8 Cylinder (1963-1995)

Exhaust Valve Lift

0.497

Intake Valve Lift

0.512

Intake Duration at .050 Inch Lift

243

Exhaust Duration at .050 inch Lift

257

Camshaft Material

Cast Iron

Kit Type

K-Kit - Complete Kit

AMAZON ASIN

B005H89WZO

Usage

Street/Performance

Assembly Lubricant Included

Yes

Lifter Type

Hydraulic Flat Tappet

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

Lifters Included

Yes

LOBE SEPARATION

107

Valve Springs Included

Yes

Camshaft Series

Thumpr

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Not sure why I had to pay tax, but very good price.

I ordered a Grant 1103 Steering Wheel, Order Number: 16767. Great prices, quick shipping, good customer service, an all around deal. Thank you.

Great product! Don't even think about another battery hold down - this one is strong, light and has the good looks to boot. Saved over $30 on it too.

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