My Account
My Garage
Shopping Cart

Shopping Cart

0 items in your Cart
View Cart
Subtotal
Track
My Order
MY GARAGE Select Vehicle
MY GARAGE

COMP Cams 31-603-5 Big Mutha Thumpr Hydraulic Flat Tappet Camshaft Ford - 243/257 221-302

(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

31-603-5
6 reviews
Sale Price

$325.95

In Stock (6)

delivery box

Usually delivered within 2 days

free shipping

FREE SHIPPING

Check out with

ApplePay
Authorize Seller Badge
No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The COMP Cams Big Mutha' Thumpr camshaft delivers an aggressive idle sound and strong performance for Ford small block 221-302 cubic inch engines. This hydraulic flat tappet camshaft features 243 degrees of intake duration and 257 degrees of exhaust duration at .050" lift, creating the signature lopey idle that muscle car enthusiasts crave while maintaining excellent street manners and reliability.

Key Specifications:

  • Intake Duration: 243° @ .050"
  • Exhaust Duration: 257° @ .050"
  • Hydraulic flat tappet design for easy maintenance
  • Optimized for Ford 221, 260, 289, and 302 cubic inch V8 engines
  • Aggressive idle with strong mid-range torque
  • Designed for street performance applications

Features & Benefits:

  • Big Mutha' Thumpr profile provides maximum idle attitude with excellent drivability
  • Hydraulic lifter design eliminates the need for valve lash adjustments
  • Split duration pattern optimizes exhaust scavenging
  • Ideal for engines with aftermarket heads, intake manifolds, and exhaust systems
  • Recommended for use with 2,000-5,800 RPM operating range
  • Requires aftermarket valve springs and compatible valve train components

This camshaft is perfect for street rods, classic Mustangs, and vintage Ford performance builds where aggressive sound and street performance are priorities. COMP Cams manufactures this camshaft from premium materials with precision grinding to ensure durability and consistent performance.

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

Grind Number

295TH7

Engine Family

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

Camshaft Material

Cast Iron

Cam and Lifter Kit Upgrade

CL31-603-5

K-Kit Upgrade

K31-603-5

AMAZON ASIN

B0046ZG72K

Assembly Lubricant Included

Yes

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.

LOBE SEPARATION

107

Camshaft Series

Thumpr

Autoplicity was quick and easy to order from. I found just what I was looking for in absolutely no time at all, plus it was shipped extremely quickly. I would definitely order from this site/company again.<br><br>Thanks!

excellent ship time and exceptional pricing deffinatly will buy from here again

Fast shipping, product was excellent .

Awesome that you can pay with Amazon!

They made a mistake with the shipping address, but, they took care of it very politely and professionally. Very nice. Thanks.

I was very happy with Autoplicity and my order of the MMRAD-MIA-90X Mishimoto radiator for my Miata. I am in the process of building a Spec-Miata for racing and trying to keep the costs down. I found Autoplicity to have the best prices on the net. I received the rad real quick. There was a problem with the radiator but the guys at Autoplicity were easy to work with and I am expecting the new radiator in a week or so.

Share icon
Return Policy
Returns are easy at THMotorsports

Not happy with a purchase? No problem. We've made returning items as easy as possible. And most purchases can be returned for free for 30 days. Learn more about our Returns Policy