GMC 283 Specs

GMC 283 engine specs: 283 ci (4.6L), 8-cylinder, 3.8748" bore x 3" stroke, 8.5:1 compression.

Dimensions

Displacement283 ci / 4.6 L
Bore3.8748"
Stroke3"
Cylinders8
Compression ratio8.5:1
Bore/stroke ratio1.292
Piston deck clearance0.014"

Construction

Block materialcast iron
Head materialcast iron
ValvetrainOHV
Fuel typegas
Advertised HP185 hp

What these numbers mean

Bore/stroke character1.292 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves
Mean piston speed at 6,000 RPM3,000 ft/min — conservative for a street engine
Displacement per cylinder35.4 ci
Static compression8.5:1 — low by modern standards, generally happy on regular pump fuel

Cylinder head

Intake valve diameter1.725"
Exhaust valve diameter1.505"
Chamber volume54.9 cc
Rocker ratio1.5:1
Lifter typehydraulic

Run the numbers for this engine

Each link opens the calculator with this engine's specs already filled in.

Vehicles (3)

Similar engines

Source: NHRA blueprints — nhra.net blueprints

← All Small Block Chevy engines