Chevrolet 265 V8 Engine

The Chevrolet 265 V8 was first introduced in 1955 and was the first small block V8 ever produced by GM. The 265 was designed for the most part to save the Corvette from being chopped due to the fact that only 700 Corvettes were sold for the 1955 model year. People were looking for something stronger than the Chevy 235 which was only good for 150 horsepower. So in just a little less than 4 months the 265 went from the drawing board to a production engine. This impressive little small block V8 produced between 162 and 195 horsepower depending on the carburetor setup and greatly helped revive the numbers of sells for the Corvette.

Although the 265 Chevy V8 did a lot for the evolution of the small block engines it was chopped for the 1957 production year and replaced by the popular Chevy 283 V8 small block. One major drawback that the 265 V8 had was that it was produced with nothing built into the block to assist with the filtration of oil. There was an oil filter that was added during production on the housing for the thermostat but it was not adequate enough to give the engine any long term durability.

Problems Associated with the 265

One major problem that GM had with the Chevy 265 was that the pistons would crack at the skirt, usually around 30k miles, causing a deep knocking noise when accelerating. The cylinders would wear a grove at the top where the piston rings stopped traveling upwards on the compression and exhaust stroke. Unfortunately, this meant that the cylinders would have to be replaced.

Another issue with the 265 was related to their camshafts which would wear out because of oil deprivation due to the oil pump not delivering sufficient oil volume and pressure. The solution to that problem was to stretch the oil pump pressure relief valve spring, hence allowing the oil pump to deliver maximum oil pressure. Usually modification of the oil pump pressure relief valve spring was only done during a rebuild after the wear and damage had already occurred.

Engine Specifications

1955 - 1957 with 2 Barrel Carb

Max Brake Horsepower: 162 @ 4400 rpm
Max Torque: 257 @ 2200 rpm
Stroke: 3.00
Bore: 3.75
Compression: 8.0
Firing Order: 18436572

1955 with 4 Barrel Carb

Max Brake Horsepower: 180 @ 4600 rpm
Max Torque: 260 @ 2800 rpm
Stroke: 3.00
Bore: 3.75
Compression: 8.0
Firing Order: 18436572

1955 with 4 Barrel Carb (Corvette Model)

Max Brake Horsepower: 195 @ 5000 rpm
Max Torque: 260 @ 3000 rpm
Stroke: 3.00
Bore: 3.75
Compression: 8.0
Firing Order: 18436572

1956 with 2 Barrel Carb (Automatic)

Max Brake Horsepower: 170 @ 4400 rpm
Max Torque: 257 @ 2400 rpm
Stroke: 3.00
Bore: 3.75
Compression: 8.0
Firing Order: 18436572

1956 with 4 Barrel Carb

Max Brake Horsepower: 205 @ 4600 rpm
Max Torque: 268 @ 3000 rpm
Stroke: 3.00
Bore: 3.75
Compression: 9.25
Firing Order: 18436572

1956 with 2 X 4 Barrel Carbs

Max Brake Horsepower: 225 @ 5200 rpm
Max Torque: 270 @ 3600 rpm
Stroke: 3.00
Bore: 3.75
Compression: 9.25
Firing Order: 18436572

1956 with 4 Barrel Carb (Corvette Model)

Max Brake Horsepower: 210 @ 5200 rpm
Max Torque: 270 @ 3200 rpm
Stroke: 3.00
Bore: 3.75
Compression: 9.25
Firing Order: 18436572

1956 with 2 X 4 Barrel Carbs (Corvette Model)

Max Brake Horsepower: 225 @ 5200 rpm
Max Torque: 270 @ 3600 rpm
Stroke: 3.00
Bore: 3.75
Compression: 9.25
Firing Order: 18436572
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