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COMP Cams 51-602-5 Big Mutha' Thumpr Hydraulic Flat Tappet Camshaft for Pontiac V8

Manufacturer

Picture for manufacturer COMP Cams

Part Number

51-602-5
10 reviews
Sale Price

$325.95

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Product Details

The COMP Cams Big Mutha' Thumpr camshaft delivers maximum performance sound and street-strip power for Pontiac V8 engines from 265 to 455 cubic inches. This hydraulic flat tappet cam features aggressive 243/257 duration specifications that produce the signature aggressive lope at idle while maintaining excellent low-end torque and mid-range punch.

Camshaft Specifications:

  • Advertised Duration: 243? Intake / 257? Exhaust
  • Duration @ .050": 218? Intake / 232? Exhaust
  • Valve Lift: .495" Intake / .519" Exhaust (with 1.5 rocker ratio)
  • Lobe Separation Angle: 107?
  • Hydraulic flat tappet design for reliable street performance

Key Features:

  • Designed specifically for Pontiac 265, 301, 326, 350, 389, 400, 421, 428, and 455 engines
  • Produces aggressive choppy idle with strong throttle response
  • Optimized for engines with aftermarket heads, intake manifolds, and exhaust systems
  • Recommended operating range: 1,800-5,800 RPM
  • Requires aftermarket converter with at least 2,400-2,800 stall speed
  • Compatible with standard hydraulic flat tappet lifters

This cam is ideal for street/strip applications where sound and performance are priorities. Best results are achieved with headers, performance intake manifold, carburetor upgrades, and upgraded valve springs. Professional installation and proper break-in procedures are strongly recommended for hydraulic flat tappet camshafts.

Products specifications

Advertised Intake Duration

295

Basic Operating RPM Range

2,500-6,400

Grind Number

295TH7

Cam Type

Hydraulic Flat Tappet

Exhaust Valve Lift

0.486

Intake Valve Lift

0.501

Intake Duration at .050 Inch Lift

243

Exhaust Duration at .050 inch Lift

257

Camshaft Material

Cast Iron

Cam and Lifter Kit Upgrade

CL51-602-5

K-Kit Upgrade

K51-602-5

AMAZON ASIN

B005H89S1C

Engine Family

Pontiac 265-455 C.I. 8 Cylinder (1955-1981)

Assembly Lubricant Included

Yes

Camshaft Gear Attachment

1-Bolt

Lifters Included

No

Valve Springs Required

Yes

Lifter Type

Hydraulic Flat Tappet

California Proposition 65

WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov

C.A.R.B. E.O. Number

N/A

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

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.

LOBE SEPARATION

107

Usage

Street/Strip

Advertised Exhaust Duration

313

Camshaft Series

Thumpr

Website was very quick and checkout through PayPal went seamlessly.

good price heavy switch

thanks for making it so easy to find my part

paypal hard to use

easy to use the amazon link to pay

Merchant agreed to resolve the issues. Items were received after 3 days and received the lowest price.

smooth experiance

Good so far

Great as always!!!

best price

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