Ford 312 V8 Engine

The Ford/Mercury 312 V8 engine was the heart and soul of the Ford Thunderbird and most Mercury models beginning in 1956. The 312 was the last of Ford’s Y-block engines. Other Y-Blocks such as the Ford 272 V8 and the Ford 292 V8 were so named due to the y-shaped cylinders.
The 312 was used in cars with 2 and 4-Barrel carburetors and was sometimes known as the “Thunderbird Special V8”. For the 1957 models, Ford dealers provided a Paxton supercharger that allowed vehicles to reach 300 horsepower. The 1956 Mercury cars contained the 312 and, depending on the model, were sold with 210, 225, 235, and even a 260 horsepower 312 engine. A special “M 260” engine kit was sold by Mercury dealers that year to boost the horsepower to 260. The kit contained two 4-barrel carburetors along with a specialized camshaft and cylinder heads.

By 1960, the 312 was reduced to a 2-barrel carburetor economy engine and phased out in 1961. The 312 remains popular, especially for 1957 Ford and Mercury model devotees.

Engine Specifications

1957 Ford Thunderbird Special 312 V8 with 4-Barrel Carb

Max Brake Horsepower: 245@ 4400 rpm
Max Torque: 332 @ 3200 rpm
Stroke: 3.44
Bore: 3.8
Compression: 9.7
Firing Order: 15486372

1957 Ford Thunderbird Supercharged 312 V8

Max Brake Horsepower: 300@ 4400 rpm
Max Torque: 327 @ 2400 rpm
Stroke: 3.44
Bore: 3.8
Compression: 8.6
Firing Order: 15486372

1956-1959 Mercury 312 V8 with 4-Barrel Carb

Max Brake Horsepower: 210@ 4600 rpm
Max Torque: 312 @ 2600 rpm
Stroke: 3.44
Bore: 3.8
Compression: 8.0, 8.4 with automatic transmission
Firing Order: 15486372
Share via