This six-cylinder engine family was first introduced in 1960 in the new Ford
Falcon automobile, intended to compete with the Volkswagon Beetle. Original engine displacement was 144 cubic
inches (3.5 bore x 2.5 stroke). This engine had four main bearings. The 144 c.i. engine size remained
in production until 1964. A 170 c.i. version with a longer stroke, (3.5 bore x 2.94 stroke), followed
in 1961, and was used as the base engine in the"new" 1964 1/2 Mustang. A seven main bearing
crankshaft support system, hydraulic lifters and a heavier distributor drive shaft became standard at
that time. A 200 c.i. version
with a longer stroke and a larger bore (3.68 bore x 3.126 stroke) followed in the 1965 model year.
A 250 cubic inch version with an even longer stroke (3.68 bore x 3.91 stroke) was introduced in 1969.
A stock seven main bearing 200 c.i. bottom end is virtually bulletproof.
This family of engines is easily identified because of the integral cast
intake manifold. The manifold looks like a cast-on log with frost plugs in each end.
The deck height on the 250's, measured from the centerline of the crankshaft
to the top of the block, was increased from 7.808" on all previous sixes, to 9.469" for an increase of
1.66". 250 engines are slightly taller because of longer stroke and connecting rods. The 250 block
is about 2" taller than a 200 block. When comparing a 170 to a 200, the block only accounts for an
increase of about 1/4", from the pan-mating surface to the head-mating surface. All engines vary in
height due to differences over the years, in valve cover, air cleaner, and oil pan configurations.
The length of this engine family remained the same, but water pumps, fans, and pulleys changed
considerably with time and applications. Because of the length of the crankshaft and inherent
six-cylinder vibration, RPM should be limited to less than 6,000.
All engines long-blocks weigh approximately 385 lb. A typical small block
Ford V8 weighs in at about 460 lb. Less weight is an important consideration in making early Falcons
and Mustangs handle and perform well.