Camshaft - Mutha' 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

Designed to deliver an aggressive, hard-hitting exhaust note at idle, the Thumpr camshaft series from COMP Cams also delivers excellent horsepower gains and a broad torque curve. A perfect choice for muscle cars and street rods, the Thumpr series' early intake valve opening and long exhaust duration create optimum overlap for that race car idle. The Thumpr grinds all require an aftermarket torque converter and lower gear ratio to ensure the drivetrain always puts the engine in its powerband. Additionally, Thumpr camshafts typically deliver reduced vacuum at idle, making a vacuum canister, pump or hydroboost a requirement for vehicles running power brakes.

Additional Information

High performance street/strip, needs 9:1 compression, 2500+ stall, intake, gears and headers, rough idle.

Application Summary

Fits '87+ GEN 1 Chevrolet 305-350 Small Blocks w/ Factory Roller Camshafts (Not LT-1/LS1 etc)

Part Type

Engine Camshaft

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.

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Product Details

Product Downloads

#	Document Type	Download
1.	Catalog

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Reference Information

Camshaft, Hydraulic Roller Tappet, Advertised Duration 291/311, Lift .522/.509, Chevy, 5.0/5.7L, Each

COMP Cams has awakened the muscle car sound--and it is nastier than ever! Thumpr Series camshafts is a line of cutting-edge hydraulic roller camshafts for engines originally equipped with flat tappet cams. With them, you can expect a substantial power increase without sacrificing reliability or ease of maintenance! The lobe profile and grind characteristics of Thumpr cams include blending an early exhaust valve opening, a long exhaust duration, and a generous amount of intake and exhaust overlap. This maximizes rough-idling tendencies, delivering a seriously aggressive exhaust note without affecting engine power output. Thumpr camshafts are available in a variety of grind profiles, each producing impressive horsepower and torque performance within a different rpm range.