COMP Cams
Big Mutha' Thumpr 243/257 Hydraulic Roller Cam for Chevrolet Small Block
UPC:
00036584148401
Availability:
This part ships direct from the manufacturer, lead times, stock and shipping may vary.
Weight:
8.77 LBS
$557.63
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Big Mutha' Thumpr 243/257 Hydraulic Roller Cam for Chevrolet Small Block
$557.63
Street/strip, needs 9.5:1 compression, 2800+ stall, intake, gears and headers, very rough idle.
This Part Fits:
This Part Fits:
Year | Make | Model | Submodel |
---|---|---|---|
1968-1971 | Jeep | J-100 | Base |
1969-1971 | Jeep | J-2500 | Base |
1969-1971 | Jeep | J-2600 | Base |
1969-1970 | Jeep | J-2700 | Base |
1969-1970 | Jeep | J-3500 | Base |
1969-1970 | Jeep | J-3600 | Base |
1969-1970 | Jeep | J-3700 | Base |
1969-1971 | Jeep | J-3800 | Base |
1968-1971 | Jeep | Wagoneer | Base |
Advertised Exhaust Duration | 319 |
Advertised Intake Duration | 299 |
Applications | Fits Chevrolet GEN 1 Small Blocks including the 262, 265, 267, 283, 302, 305, 307, 327, 350 and 400. Does not fit LT1/LT4, or factory roller Small Blocks built from 1985 and newer. GM gradually added roller camshafts to 305's and 350's from the mid 80's forward. Camaros/Firebirds/Corvettes received the roller cams early, but many trucks and SUV's had flat tappet cams until the mid 90's. Remove the intake or timing cover to confirm whether the block is a factory roller or flat tappet. Does not fit the LS1, LS2, LS3 or any LS-based 4.8, 5.3, 5.7, 6.0 and 6.2. 1955-1957 Chevrolet 265 engines require a groove on the 5th cam journal for oiling. Contact us for more information. |
Assembly Lubricant Included | No |
Basic Operating RPM Range | 2,500-6,200 |
C.A.R.B. E.O. Number | N/A |
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. |
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. Exemption Reason | N/A |
California Proposition 65 | WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov |
Cam and Lifter Kit Upgrade | CL12-602-8 |
Cam Type | Hydraulic Roller |
Cam, Lifter and Gear Drive Upgrade | GK12-602-8 |
Camshaft Gear Attachment | 3-Bolt |
Camshaft Material | Austempered Ductile Iron |
Camshaft Series | Thumpr |
Description | Street/strip, needs 9.5:1 compression, 2800+ stall, intake, gears and headers, very rough idle. |
Engine Family | Chevrolet 262-400 c.i. 8 Cylinder (1958-1998) |
Exhaust Duration at .050 inch Lift | 257 |
Exhaust Valve Lift | 0.517 |
Grind Number | 299THR7 |
Intake Duration at .050 Inch Lift | 243 |
Intake Valve Lift | 0.531 |
K-Kit Upgrade | K12-602-8 |
Lifter Type | Hydraulic Roller |
Lifters Included | No |
Lobe Separation | 107 |
Usage | Street/Strip |
Valve Springs Required | Yes |