Engines and Components› Camshafts and Valvetrain

COMP Cams

Thmpr NIT 243/257 H-Flt Cam BBC 396-454

$410.26

SKU: C007 11-602-20

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Overview

The COMP Cams 11-602-20 is a Big Mutha' Thumpr Hydraulic Flat Tappet Camshaft designed for street/strip applications in Chevy Big Block engines. It features a nitrided finish for durability, produces a very rough idle, and requires supporting modifications like 9.5:1 compression, a 2800+ stall converter, intake, gears, and headers. It has an advertised duration of 295 intake / 312 exhaust and a duration at 0.050 inch lift of 243 intake / 257 exhaust. Intake valve lift is 0.522 inches, and exhaust valve lift is 0.507 inches.
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Part #: 11-602-20

Big Mutha' Thumpr Nitrided 243/257 Hydraulic Flat Cam for Chevrolet Big Block 396-454. Street/strip, needs 9.5:1 compression, 2800+ stall, intake, Gear and headers, very rough idle.

Street/strip, needs 9.5:1 compression, 2800+ stall, intake, gears and headers, very rough idle. Nitrided.

This product may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.

Vehicle Symptoms
  • Rough loping idle that sounds like a race car
  • Loss of low-end torque for daily driving
  • Engine stalls or struggles at low RPMs
  • Lack of power above 3000 RPM on highway
  • Exhaust note sounds choppy or uneven
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Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandCOMP Cams
Part NumberC007 11-602-20
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