Buick 400 Specs

Buick 400 engine specs: 400 ci (6.6L), 8-cylinder, 4.126" bore x 3.7992" stroke, 10.25:1 compression.

Dimensions

Displacement	400 ci / 6.6 L
Bore	4.126"
Stroke	3.7992"
Cylinders	8
Compression ratio	10.25:1
Bore/stroke ratio	1.086

Construction

Block material	cast iron
Head material	cast iron
Valvetrain	OHV
Fuel type	gas
Advertised HP	340 hp

What these numbers mean

Bore/stroke character	1.086 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves
Mean piston speed at 6,000 RPM	3,799 ft/min — in the range typical of performance street engines
Displacement per cylinder	50.0 ci
Static compression	10.25:1 — in the range that usually runs on pump premium

Run the numbers for this engine

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

• Displacement calculator
• Compression ratio calculator
• Piston ring gap calculator
• Piston speed calculator
• Carburetor CFM calculator

Vehicles (7)

• Buick GS 400
• Buick Riviera
• Buick Wildcat
• Buick Electra
• Buick Sport Wagon
• GS 400
• Sport Wagon

Similar engines

• Buick 430 — 430 ci
• Buick 455 — 455 ci
• Buick Buick 400ci · 4.188" × 3.64" · 10.25:1 — 400 ci
• Buick Buick 400ci · 4.188" × 3.64" · 11:1 — 400 ci
• Buick Buick 400ci · 4.04" × 3.9" · 10.25:1 — 400 ci
• Buick 401 — 401 ci
• Chevrolet Chevrolet 400ci · 4.125" × 3.750" · 9.201:1 — 400 ci
• Chevrolet Chevr 1973 400 150HP — 400 ci

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