COMP Cams CL12-602-4 Big Mutha' Thumpr Hydraulic Flat Tappet Cam and Lifter Kit for Chevy Small Block Engines [Duration 243/257 @ .050]
249-CL12-602-4
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| Ratings |
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| Price |
| Brand |
Chevy 262-400ci Small Block 1958-98
Comp Cams CL12-602-4 Big Mutha' Thumpr Hydraulic Flat Tappet Cam and Lifter Kit:
- Very rough, lopey idle
- Long exhaust duration produces a powerful hard-hitting exhaust note
- Excellent horsepower gains and broad torque curve
- Grind Number: 295TH7
- Cam Type: Hydraulic Flat Tappet
- Lifter Style: Hydraulic Flat Tappet
- Advertised Intake Duration: 295
- Advertised Exhaust Duration: 313
- Intake Duration at .050 in. Lift: 243
- Exhaust Duration at .050 in. Lift: 257
- Intake Valve Lift: .500 in.
- Exhaust Valve Lift: .486 in.
- Lobe Separation: 107
- Camshaft Gear Attachment: 3-Bolt
- Requires:
- 9.5:1 compression
- 2800 or up stall stall converter
- Aftermarket intake
- Lower differential gear ratio
- Headers
FAQ
What lift is a Mutha Thumpr cam?
- The Comp Cams CL12-602-4 Mutha Thumpr cam has a lift of 0.500/0.486 inches.
- This lift profile enhances valve movement for increased performance.
What is a thumper cam?
- A thumper cam, like the Big Mutha' Thumpr 243/257 hydraulic flat cam/lifter kit, features an aggressive idle.
- It provides a distinct, lopey sound, emphasizing performance characteristics.
What are the specs on a Mutha Thumpr cam?
- The Comp Cams CL12-602-4 offers a duration of 243/257 at .050" lift with a 0.500-0.486 lift range.
- Designed for improved low-end torque and high-end horsepower.
Do cam kits come with lifters?
- Yes, the Big Mutha' Thumpr 243/257 hydraulic flat cam/lifter kit (CL12-602-4) includes lifters for a comprehensive installation.
Specifications:
Part Type
Product Line
Advertised Duration
295 int./313 exh.
Advertised Exhaust Duration
313
Advertised Intake Duration
295
Assembly Lubricant Included
Yes
Basic Operating RPM Range
2,500-6,400
Cam Style
Hydraulic flat tappet
Camshaft Gear Attachment
3-bolt
Computer-Controlled Compatible
No
Duration at 050 inch Lift
243 int./257 exh.
Engine Make/Size
Chevy Small Block (262-400)
Exh. Duration @ .050 in. (Deg)
257
Exh. Duration Advertised (Deg)
313
Exhaust Duration at 050 inch Lift
257
Exhaust Valve Lift
0.486 in (12.344 mm)
Exhaust Valve Lift with Factory Rocker Arm Ratio (
0.486
Gaskets Included
No
Grind Number
295TH7
Int. Duration @ .050 in. (Deg)
243
Int. Duration Advertised (Deg)
295
Intake Duration at 050 inch Lift
243
Intake Valve Lift
0.5 in (12.7 mm)
Intake Valve Lift with Factory Rocker Arm Ratio (i
0.5
Lifter Style
Hydraulic flat tappet
Lifter Type
Hydraulic Flat Tappet
Lifters Included
Yes
Lobe Separation (Deg)
107
Locks Included
No
Package Depth
3.10
Package Height
25.40
Package Width
5.60
Part Category
Performance Parts
Part Fitment
Semi Universal
Pushrods Included
No
Quantity
Sold as a kit
RPM Range
2500-6400
Retainers Included
No
Rocker Arms Included
No
Shipping Weight
13.35
Timing Chain and Gears Included
No
Usage
Street/Strip
Valve Lift with Factory Rocker Arm Ratio
0.500 int./0.486 exh.
Valve Springs Included
No
Valve Springs Required
Yes
Valve Stem Seals Included
No
Vendor Part Number
CL12-602-4
CL12-602-4 - Comp Cams Thumpr Hydraulic Flat Tappet Cams is rated
out of
5 by
10.
Rated 5 out of
5
by
just me from
thump cam
I finally installed cam and started engine. Runs and sounds great, got another 350 to build will put in another one.
Date published: 2024-03-25
Rated 5 out of
5
by
ADAM from
-BIG THUMPR- CL12-602-4
GREAT SOUND AND THE BEST ALL AROUND FROM BOTTOM END TO TOP END PERFORMANCE IVE FOUND FOR MY SET UP..
I HAD TO ADD A ELECTRIC VACUUM PUMP, BUT ALL APPLICATIONS MAY NOT NEED ONE.
5 STARS IN MY BOOK âï¸âï¸âï¸âï¸âï¸
Date published: 2022-10-30
Rated 5 out of
5
by
Monga Man from
Wow!!!!!!!
Can't believe my little 355 runs and sounds like this.
Date published: 2021-12-15
Rated 5 out of
5
by
1986 Toyota pickup from
Love it
I absolutely love this cam. I'm running it in a 383 stroker an im amazed with it. Definitely will buy another one..... Thanks Comp
Date published: 2020-08-10
Rated 2 out of
5
by
just me from
thump cam
I haven't installed it yet. shipping box was crushed and cam had fallen out of shipping box. lifters had shifted inside box, and there was no assembly lube with the cam.
Date published: 2023-07-09
Do I need a different distributor gear for this cam
COMP Cams CL12-602-4 will work with a stock distributor gear.
Date published: 2025-04-24
What valve springs are recommended for this camshaft?
The Comp 249-CL12-602-4 cam uses Comp 249-26987-16 springs
Date published: 2025-04-10
Would this camshaft work for a 1986 Chevrolet Corvette with the L98 Tune Port Injection?
COMP Cams CL12-602-4 will not fit a '86 Corvette. It will not work with the stock computer.
Date published: 2025-03-04
Hi, I haven’t heard this cam and new lifters. My question is how much laddifionsl lift would a 1.6 rocker make? I am happy with the cam but just want more lift and lopey idle
The Comp 249-CL12-602-4 cam will be .553/.478 lift with 1.6 rockers.
Date published: 2025-01-16
Will this fit a 1998 chevy k1500 305 5.0L?
COMP Cams CL12-602-4 will not fit a 98 Chevy K1500 305. It will not work with the stock computer.
Date published: 2024-11-26
Does this have a lobe for the fuel pump ?
Yes, COMP Cams CL12-602-4 Has a mechanical fuel pump lobe.
Date published: 2024-11-14
What distributor does this cam require
The Comp 249-CL12-602-4 cam uses a standard Chevy distributor.
Date published: 2024-10-08
What class/stage is this cam And will this a 5.7 350 Chevy c1500
The Comp 249-CL12-602-4 cam kit does not have a 'stage' name associated with it.
Date published: 2024-08-27
Complete Kit3 Grinds To Fit All Of Your Performance NeedsLong Exhaust DurationProduces A Powerful Hard-Hitting Exhaust NoteExcellent Horsepower Gains And Broad Torque CurveDelivers Real Seat Of The Pants PerformanceDesigned For Use w/Latest In ValveTrain Components1 Year Limited WarrantyBuick; Buick 350; ...
Nitrided265, 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, ...
Complete Kit3 Grinds To Fit All Of Your Performance NeedsLong Exhaust DurationProduces A Powerful Hard-Hitting Exhaust NoteExcellent Horsepower Gains And Broad Torque CurveDelivers Real Seat Of The Pants PerformanceDesigned For Use w/Latest In ValveTrain Components1 Year Limited Warranty265, 283, 307, ...
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