Ford MEL engine

Ford developed the MEL ("Mercury-Edsel-Lincoln") engine series as the replacement for the Lincoln Y-block V8 engine for use in large passenger car applications. These engines were produced in Lima, Ohio at Ford's Lima Engine plant. They were in turn replaced by the 385 series engines.

All MEL engines had wedge-shaped combustion chambers formed between a flat head surface and an angle milled block deck (10 degrees off square with the bore axis), with the piston top determining the compression ratio and combustion chamber shape, similar to the Chevrolet Big-Block 348 combustion chamber, also introduced in 1958, and the later 409 and 427. Unlike the Chevrolet, which had staggered valves and scalloped or M-shaped valve covers, the MEL valves were inline with shaft mounted rocker arms like the FE model Ford engines which were introduced at the same time. As with the previous generation V8s, an open runner intake manifold was used, requiring the use of a stamped steel lifter valley cover similar to that of the Pontiac V8 engines. Also, the intake manifold provided no exhaust crossover passage to warm the air-fuel mixture. Further MEL engines employed two individual thermostats, aimed to improve the regulation of the engine's coolant temperature. It was introduced the same year Chrysler phased out the Hemi V8 for the Chrysler B engine which was also a wedge-shaped combustion chamber.

The MEL bore some mechanical similarities with the Ford FE, using similar components such as the oiling system, bolt patterns, and valve stems; however, the MEL was a Lincoln-specific engine and was even larger in displacement capacity. The main bearings were 73.66 mm (2.900 in), while the rod bearings were 66.04 mm (2.600 in). The connecting rod beam had a unique triangular shape with the shoulders for the bolts sitting low toward the cap mating surface 1⁄2 in (13 mm). There was one major difference between the MEL and FE engines besides their size and weight; the valves on MEL engines were arranged in alternating fashion (I-E-I-E-I-E-I-E) and not in the manner of the FE (E-I-E-I-I-E-I-E) where the I indicates an intake valve and the E indicates an exhaust valve.

The MEL was one of three new engine families introduced by Lincoln and Ford in 1958. The others were the FE (Ford Edsel) and SD (super duty), the latter being large and extra powerful, slow-revving engines engineered for heavy-duty work trucks. The FE engine saw its use in the Edsel, a model which was introduced to the vehicle lineup by Ford, described as a car which blended design features of the Ford and Mercury lines combining them with its own individual styling. Further several new Lincoln vehicles, such as the Continental luxury sedan and coupe, as well as the all-new four-seat Thunderbird of the same year, which were brought to market with the new engines.