COMP Cams Big Mutha" Thumpr Hydraulic Flat Tappet Camshaft and Lifter Kit Lift .512"/.497" Duration 295/312 RPM Range 2500-6400
249-CL31-603-5

Items You Need
Ford 289-302 C.I. 8 cyl. 1963-1995
Ford; SBF; Mustang; Windsor; Fairlane; Meteor; Mercury; GT; 22; 260; Sunbeam; Tiger; 289; 302; 351; 289; HiPo; K-Code; GT-350; Shelby; Boss; 5.0; 308; Windsor; Torino; Cougar; F-150; Squire; Thunderbird; LTD; Galaxie; Grand Marquis
Street/strip, needs 9.5:1 compression, 2800+ stall, intake, gears and headers, very rough idle.
Specifications:
Thumpr Camshafts are the hottest cams to hit the streets in more than a decade. That's because they give you the big cam sound you're looking for, without the drawbacks. Applying a camshaft design originally created for sports car endurance racing, they incorporate early exhaust valve opening, long exhaust duration, and a generous amount of intake and exhaust overlap. Best of all, Thumprs will not negatively impact power output or streetability.
Features:![]() Thumpr Sound Clip ![]() |
Camshaft & Lifter Kits are indicated by a CL in their part number and include Camshaft, Lifters, Assembly Lube, Decals, and Instructions.
Complete Kits are indicated by a K in their part number and include Camshaft, Lifters, Timing Chain & Gears, Valve Springs, Retainers, Locks, Assembly Lube, Decals, and Instructions.
Does COMP Cams CL31-603-5 fit your vehicle?
1974 FORD GRAN TORINO
- Liter: 7.5
- SubModel: BASE
- Aspiration: NATURALLY ASPIRATED
- CUI: 460
- Engine Type: V8 ( 7.5L / 460 )
- Engine Vin: A
1985 MERCURY GRAND MARQUIS
- Liter: 5
- SubModel: LS
- Aspiration: NATURALLY ASPIRATED
- CUI: 302
- Engine Type: V8 ( 5L / 302 )
- Engine Vin: F
1970 FORD FAIRLANE
- Liter: 5
- SubModel: 500
- Aspiration: NATURALLY ASPIRATED
- CUI: 302
- Engine Type: V8 ( 5L / 302 )
- Engine Vin: F
1969 FORD GALAXIE 500
- Liter: 7
- SubModel: XL
- Aspiration: NATURALLY ASPIRATED
- CUI: 429
- Engine Type: V8 ( 7L / 429 )
- Engine Vin: K
1964 FORD BRONCO
- Liter: 4.7
- SubModel: ROADSTER
- Aspiration: NATURALLY ASPIRATED
- CUI: 289
- Engine Type: V8 ( 4.7L / 289 )
- Engine Vin: C
1973 FORD MUSTANG
- Liter: 5.8
- SubModel: BASE
- Aspiration: NATURALLY ASPIRATED
- CUI: 351
- Engine Type: V8 ( 5.8L / 351 )
- Engine Vin: H
1974 FORD BRONCO
- Liter: 5.8
- SubModel: CUSTOM
- Aspiration: NATURALLY ASPIRATED
- CUI: 351
- Engine Type: V8 ( 5.8L / 351 )
- Engine Vin: H
1970 FORD COUNTRY SQUIRE
- Liter: 3.9
- SubModel: BASE
- Aspiration: NATURALLY ASPIRATED
- CUI: 240
- Engine Type: L6 ( 3.9L / 240 )
- Engine Vin: E
1966 MERCURY CYCLONE
- Liter: 7
- SubModel: BASE
- Aspiration: NATURALLY ASPIRATED
- CUI: 427
- Engine Type: V8 ( 7L / 427 )
- Engine Vin: R
1970 FORD RANCH WAGON
- Liter: 3.3
- SubModel: BASE
- Aspiration: NATURALLY ASPIRATED
- CUI: 200
- Engine Type: L6 ( 3.3L / 200 )
- Engine Vin: T
1968 FORD FAIRLANE
- Liter: 6.4
- SubModel: 500
- Aspiration: NATURALLY ASPIRATED
- CUI: 390
- Engine Type: V8 ( 6.4L / 390 )
- Engine Vin: H
1971 FORD COUNTRY SEDAN
- Liter: 7
- SubModel: BASE
- Aspiration: NATURALLY ASPIRATED
- CUI: 429
- Engine Type: V8 ( 7L / 429 )
- Engine Vin: K
Will I need a new timing chain and timing gears?
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Electrical Cords
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