Description
Camshaft - Thumpr - Hydraulic Roller - Lift 0.522 / 0.509 in - Duration 291 / 311 - 107 LSA - 2200 / 5900 RPM - Small Block Chevy - Each
MT 235/249 HRlrSBC
WARNING: Camshaft Optimized for use with a Melanized or Nitrided distributor Gear. Not compatible with cast or Steel Gears without similar surface treatments. Failure to utilize the proper distributor Gear will void all warranties and/or return policies.
Additional Information
High performance street/strip, needs 9:1 compression, 2500+ stall, intake, gears and headers, rough idle.
Application Summary
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.
Part Type
Engine Camshaft
Product Overview
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.
| Additional Application Notes | |
|---|---|
| • Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
| • w/ V Engine VIN; | |
| • w/ V Engine VIN; Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
| • w/ H Engine VIN; | |
| • w/ H Engine VIN; Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
| • From 1985-1998 Chevrolet introduced the factory roller Small Block into GM cars and trucks. Verify whether or not your vehicle came with a factory roller camshaft. If your vehicle was equipped with a roller camshaft, look to our camshafts and kits that start with "08-". | |
| • w/ T Engine VIN; w/ L Engine VIN; | |
| • w/ T Engine VIN; w/ L Engine VIN; Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
| • w/ S Engine VIN; | |
| • w/ S Engine VIN; Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
| • w/ L Engine VIN; | |
| • w/ L Engine VIN; Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
| • w/ T Engine VIN; | |
| • w/ T Engine VIN; Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
| • w/ R Engine VIN; | |
| • w/ R Engine VIN; Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
| • w/ L Engine VIN; w/ K Engine VIN; | |
| • w/ L Engine VIN; w/ K Engine VIN; Retro-Fit Hyd. Roller; 2200-5900rpm; Adv. Dur. 291 Int./311 Exh.; Valve Lift .521 Int/.507 Exh.; Lobe Angle 107 deg.; Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle | |
These additional application notes are supplied by the manufacturer and collated from multiple year ranges. Not all of these notes may apply to every year or every variant. Please contact a StreetFX agent for clarification if required.
Features
Images are supplied by the manufacturer and may be generic. While all efforts are made to provide accurate pictures, there may be differences in the actual product, such as colour, quantity, version, or included components. Please carefully review the description and specifications for details on inclusions or any variations. Some items may be sold individually or in sets, and images may occasionally depict additional products or quantities not included in your purchase. For assistance or clarification, please contact customer support.
Specifications
Product Details
| Advertised Exhaust Duration: | 311 |
| Advertised Intake Duration: | 291 |
| Amazon ASIN: | B0014F4Q96 |
| Assembly Lubricant Included: | No |
| Basic Operating RPM Range: | 2,200-5,900 |
| 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. |
| Cam Type: | Hydraulic Roller |
| Cam and Lifter Kit Upgrade: | CL12-601-8 |
| Cam, Lifter and Gear Drive Upgrade: | GK12-601-8 |
| Camshaft Gear Attachment: | 3-Bolt |
| Camshaft Material: | Austempered Ductile Iron |
| Camshaft Series: | Thumpr |
| Description: | Mutha' Thumpr 235/249 Hydraulic Roller Cam for Chevrolet Small Block |
| Engine Family: | Chevrolet 262-400 c.i. 8 Cylinder (1958-1998) |
| Exhaust Duration @ .050 in.: | 249 |
| Exhaust Duration at .050 inch Lift: | 249 |
| Exhaust Duration: | 311 |
| Exhaust Valve Lift(in): | 0.507 |
| Exhaust Valve Lift: | 0.507 |
| Grind Number: | 291THR7 |
| Intake Duration @ .050 in.: | 235 |
| Intake Duration at .050 Inch Lift: | 235 |
| Intake Duration: | 291 |
| Intake Valve Lift(in): | 0.521 |
| Intake Valve Lift: | 0.521 |
| K-Kit Upgrade: | K12-601-8 |
| Lifter Type: | Hydraulic Roller |
| Lifters Included: | No |
| Part Number: | cca12-601-8 |
| RPM Range: | 2000-9000 |
| Title: | Mutha' Thumpr 235/249 Hydraulic Roller Cam for Chevrolet Small Block |
| Usage: | Street/Performance |
| Valve Springs Required: | Yes |
Product Downloads
Installation guides, warranty details, and other supporting documents are provided by the supplier. In some cases, these files may originate from regions outside your locale, meaning instructions, warranty procedures, and images may not fully align with your specific vehicle or region (e.g., LHD vs. RHD differences, return policies, etc.). If you need clarification, please contact a StreetFX support agent.
Reference Information
| Reference Data (Provide these details to our support team) | |
|---|---|
| Brand Name/s | Comp Cams, Comp Cams (edelbrock) |
| StreetFX SKU | cca12-601-8 |
| SFX Item ID | 4118736 |
| Accounting SKU | cca-12-601-8 |
| Manufacturer SKU | 12-601-8 |
| Manufacturer UPC | 036584148395 |
| Alternative References | 12-601-8, CCA-12-601-8, COM12-601-8 |
Camshaft, Hydraulic Roller Tappet, Advertised Duration 291/311, Lift .521/.507, Chevy, Small Block, Each
COMP Cams is bringing back the musclecar sound—and it's nastier than ever! Few things grab our attention at a car show or cruise night more than a car with a thumping high performance idle. In an ongoing quest to provide you with the performance and sound you demand, COMP Cams' engineering team proudly introduces the Thumpr retrofit hydraulic roller camshafts. They are a series of camshafts designed for use in engines that were originally equipped with flat tappet camshafts. The lobe profile and grind characteristics use a combination of an early exhaust valve opening, a long exhaust duration, and a generous amount of intake and exhaust overlap to maximize the rough-idling characteristics of the cams. They give you a seriously aggressive exhaust note without negatively impacting the power output or streetability of the engine. Thumpr camshafts are available in three different grind profiles. Each one will produce a rough, racy exhaust note and impressive amounts of horsepower and torque within a different rpm range. COMP Cams Thumpr Series camshafts feature a cutting-edge hydraulic roller design that delivers a substantial power increase over identical hydraulic flat tappet grinds—without sacrificing reliability or ease of maintenance.
| Product Attributes | |
|---|---|
| Brand | COMP Cams |
| Manufacturer's Part Number | 12-601-8 |
| Part Type | Camshafts |
| Product Line | COMP Cams Thumpr Retrofit Hydraulic Roller Camshafts |
| UPC | 036584148395 |
| Cam Style | Hydraulic roller, Retro-fit |
| Camshaft Use | Street/Strip |
| Basic Operating RPM Range | 2,200-5,900 |
| Intake Duration at 050 inch Lift | 235 |
| Exhaust Duration at 050 inch Lift | 249 |
| Duration at 050 inch Lift | 235 int./249 exh. |
| Advertised Intake Duration | 291 |
| Advertised Exhaust Duration | 311 |
| Advertised Duration | 291 int./311 exh. |
| Intake Valve Lift with Factory Rocker Arm Ratio | 0.522 in. |
| Exhaust Valve Lift with Factory Rocker Arm Ratio | 0.509 in. |
| Valve Lift with Factory Rocker Arm Ratio | 0.522 int./0.509 exh. |
| Remanufactured | No |
| Computer-Controlled Compatible | No |
| Grind Number | 291THR7 |
| Valve Springs Required | Yes |
| Quantity | Sold individually. |
| Notes | Designed for engines originally equipped with flat tappet camshaft. |
Compatibility
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