COMP Cams Big Mutha" Thumpr Hydraulic Flat Tappet Camshaft Pro-Plasma Nitrided Lift .500"/.486" Duration 295/313 RPM Range 2500 to 6500
249-12-602-20

Chevy 262-400ci Small Block 1958-98
265, 283, 307, 302, 305, 327, 350, 383, 400, 427, L46, L48, L65, LM1, LT-1, L82, L81, LS9, L83, L98, L05, LG3, LG4, LT1, LT4, Camaro, Corvette, Chevelle, Stingray, Silverado, C10, Firebird, Chevrolet, Chevy, Small Block Chevy, Caprice, Malibu, Impala, Nova, 355, GEN1, Monte Carlo, S10
Street/strip, needs 9.5:1 compression, 2800+ stall, intake, gears and headers, very rough idle. Nitrided.
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 12-602-20 fit your vehicle?
1980 GMC K1500 SUBURBAN
- Liter: 5.7
- SubModel: BASE
- Aspiration: NATURALLY ASPIRATED
- CUI: 350
- Engine Type: V8 ( 5.7L / 350 )
- Engine Vin: M
1978 CHEVROLET CAPRICE
- Liter: 5
- SubModel: CLASSIC
- Aspiration: NATURALLY ASPIRATED
- CUI: 305
- Engine Type: V8 ( 5L / 305 )
- Engine Vin: U
1981 GMC C1500 SUBURBAN
- Liter: 5
- SubModel: SIERRA CLASSIC
- Aspiration: NATURALLY ASPIRATED
- CUI: 305
- Engine Type: V8 ( 5L / 305 )
- Engine Vin: F
1970 CHEVROLET CAMARO
- Liter: 5.7
- SubModel: Z28
- Aspiration: NATURALLY ASPIRATED
- CUI: 350
- Engine Type: V8 ( 5.7L / 350 )
- Engine Vin: -
1975 CHEVROLET C20 SUBURBAN
- Liter: 5.7
- SubModel: SILVERADO
- Aspiration: NATURALLY ASPIRATED
- CUI: 350
- Engine Type: V8 ( 5.7L / 350 )
- Engine Vin: V
1977 GMC K15 SUBURBAN
- Liter: 6.6
- SubModel: SIERRA GRANDE
- Aspiration: NATURALLY ASPIRATED
- CUI: 400
- Engine Type: V8 ( 6.6L / 400 )
- Engine Vin: R
1991 CHEVROLET K1500
- Liter: 5.7
- SubModel: SPORT
- Aspiration: NATURALLY ASPIRATED
- CUI: 350
- Engine Type: V8 ( 5.7L / 350 )
- Engine Vin: K
1981 CHEVROLET C20 SUBURBAN
- Liter: 5
- SubModel: DELUXE
- Aspiration: NATURALLY ASPIRATED
- CUI: 305
- Engine Type: V8 ( 5L / 305 )
- Engine Vin: H
1979 GMC K3500
- Liter: 5.7
- SubModel: HIGH SIERRA
- Aspiration: NATURALLY ASPIRATED
- CUI: 350
- Engine Type: V8 ( 5.7L / 350 )
- Engine Vin: M
1992 GMC K2500
- Liter: 5
- SubModel: SIERRA
- Aspiration: NATURALLY ASPIRATED
- CUI: 305
- Engine Type: V8 ( 5L / 305 )
- Engine Vin: H
1966 CHEVROLET CHEVY II
- Liter: 4.6
- SubModel: NOVA SS
- Aspiration: NATURALLY ASPIRATED
- CUI: 283
- Engine Type: V8 ( 4.6L / 283 )
- Engine Vin: -
1972 CHEVROLET G20 VAN
- Liter: 5.7
- SubModel: SPORTVAN
- Aspiration: NATURALLY ASPIRATED
- CUI: 350
- Engine Type: V8 ( 5.7L / 350 )
- Engine Vin: E
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