GM Performance Parts ZZ383 Engine

Product images may differ from actual product appearance.

Big Block Performance,
Small Block Price Tag

It all starts with a 383 cubic inch block and the legendary Fast Burn cylinder heads, offering an incredible 460 ft/lbs of torque @ 4500 RPM with a smooth linear delivery. The combination of a 4.000" bore and 3.750" stroke steel crank and a stout .509"/.528" lift hydraulic roller camshaft produces 425 HP @ 5400 RPM. GM testing utilized a single plane intake manifold (#809-12496822), Demon 750 cfm mechanical secondary carb, and 1-3/4" primary x 33" long headers with 4" collectors. A dual plane manifold (#809-12366573) can be used but will affect overall peak performance by 15-20 horsepower.

Specifications

Horsepower: 425 @ 5400 RPM

Torque: 449 ft/lbs @ 4500 RPM

Compression Ratio: 9.7:1

Block: Cast Iron 4-Bolt Main with 1-piece rear main seal

Crankshaft: Forged 4340 Steel (externally balanced)

Connecting Rods: Powdered Metal (special 383 version)

Pistons: Hypereutectic Flat Top with offset pins

Camshaft: Hydraulic roller, 222°/230° @ .050", .509"/.528" lift, 112° center lobe

Rockers: 1.5:1 Aluminum full roller self-aligning

Cylinder Heads: Aluminum Fast Burn 62cc chamber, 210cc intake runners, 2.00" hollow stem intake/1.55" sodium-filled exhaust valves, LT4 Corvette valve springs and lightweight retainers,
D-shaped exhaust ports, dual intake bolt pattern, and standard & centerbolt valve cover patterns

Additional Parts Included

8" balancer

12-3/4" automatic flexplate

4-quart oil pan with windage tray (5-quart capacity with PF35 filter)

Painted valve covers with oil cap (provisions for PCV breather)

Composite plastic front timing cover

Engine oil dipstick and tube (passenger side)

Brass freeze plugs

Fuel pump block-off plate

Engine lift tabs

Recommended Components

Long, cast iron water pump (standard V-belt rotation with 1979-86 power steering pump boss)

Vortec Single Plane Manifold #809-12496822 (to achieve 425 HP)

Vortec Dual Plane Manifold #809-12366573 (when hood clearance is a problem; peak power may decrease 15-20 HP)

Warranty Information