what year did the 255 cubic inch engine come out?

Answer 1

Flathead Specifications

Late 90-125hp V8: 1949 to 1953


The Strato-Star EAB V8 for 1953
(shown above)
Major changes occurred to the mid size flathead V8 in 1948 for the new Ford trucks and in 1949 for new Ford and Mercury cars. The new engine incorporated several changes, some obvious and some not. The heads are now bolted to the blocks with 24 bolts (rather than studs and nuts) and the water outlet fittings are moved up to the front corner of the head (rather than the middle of the head). Another major change was the use of the new "Load-A-Matic" distributor, which was driven off the front of the engine, but through a shaft mounted vertically at right angle to the axis of the engine. With this new engine, Ford stopped casting the bell housing integral to the cylinder block, and provided it as a separate component which was bolted on. Internal changes include using a straight stem valve with one-piece valve guide. The belts and pulleys for 1948/49 stayed with the 5/8" wide of previous years, but changed from 1950 on to the narrow belts. In general, the latter year flatheads were commonly referred to as the "8BA" type for Ford and "8CM" for Mercury. The truck version was identified as an "8RT". Later 1952 and '53 Fords and Mercurys were known as "EAB" and "EAC" respectively. These markings are generally cast into the cylinder heads. The truck versions often had different oil pans to accommodate the different suspensions, and some truck V8's were factory "relieved". The EAB's and EAC's did not have the hardened valve seat inserts like the earlier engines.
Year Displacement
(Cubic Inches) Bore & Stroke
(Inches) Maximum
Brake HP Compression Ratio Head Bolts Notes
1949 Ford 239 3.1875 x 3.750 100 6.80:1 24 2
1949 Mercury 255 3.1875 x 4.000 110 6.80:1 24 3,1

Answer 2

Ford's final flathead was the 1948-1953 239/255. The 255 was achieved by use of a 4 inch stroke crankshaft in the Mercury engines, producing 125 hp and making the merc crank a popular upgrade for hot rodders.

While earlier Ford V8s had the distributor driven directly from the forward end of the camshaft, and so at an inconvenient location for maintenance, this final flathead used a right angle gear drive from the camshaft, placing the distributor atop the engine near the front and so readily accessible. The fuel pump was mounted centrally atop the rear of the engine, driven by a reciprocating pushrod from a lobe on the camshaft.

Answer 3

In the golden era of the 1950s and early 1960s, the standard sprint car engine was the classic double-overhead-cam, 4-valve-per-cylinder, 4-cylinder Offenhauser. The 255-cubic-inch Offys made a low-pitched guttural roar that few who ever heard it have forgotten.

Answer 4

1980 and they've stopped making them in 1982.