Description

Thumpr NIT 235/249 Hydraulic Flat Cam for Chevrolet Big Block 396-454Designed to deliver an aggressivehard-hitting exhaust note at idlethe Thumpr camshaft series from COMP Cams also delivers excellent horsepower gains and a broad torque curve. A perfect choice for muscle cars and street rodsthe 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. AdditionallyThumpr camshafts typically deliver reduced vacuum at idlemaking a vacuum canisterpump or hydroboost a requirement for vehicles running power brakes.

Advertised Exhaust Duration: 304 DD

Advertised Intake Duration: 287 DD

Assembly Lubricant Included: Yes

Basic Operating RPM Range: 2 000-5 900 R3

Cam Type: Hydraulic Flat Tappet

Camshaft Gear Attachment: 3-Bolt

Camshaft Material: Nitrided Cast Iron

Camshaft Series: Thumpr

Engine Family: Chevrolet 396-454 c.i. 8 Cylinder (1967-1996)

Exhaust Duration at .050 inch Lift: 249 DD

Exhaust Valve Lift: 0.495″

Grind Number: 287TH7

Intake Duration at .050″ Lift: 235 DD

Intake Valve Lift: 0.51″

Lifter Type: Hydraulic Flat Tappet

Lifters Included: No

Lobe Separation: 107 DD

Usage: Street/Strip

Valve Springs Required: Yes