Leyland Engines, lorry, truck and van engines, Wolseley 2200, Austin 18-22, Morris
Leyland produced car engines
with a Pushrod Straight-4 and a SOHC Straight-6, all their models were:
Wolseley 2200, Austin 18-22, Morris
18-22, Leyland Princess and the Leyland Princess 2. Engines and gearboxes provide reconditioned, used or secondhand Leyland engines.
They also produce lorry, truck and van engines!
A pushrod engine or I-head
engine is a type of piston engine that places the camshaft in the cylinder
block (usually beside and slightly above the crankshaft in a straight engine or
directly above the crankshaft in the V of a V engine) and uses pushrods or rods
to actuate rocker arms above the cylinder head to actuate the valves. Lifters or
tappets reside in the engine block between the camshaft and pushrods.
This contrasts with an overhead cam (OHC) design which places the camshafts above
the cylinder head and drives the valves directly or through short rocker arms. In
an OHC engine, the camshafts are normally part of the cylinder head assembly, while
in an I-head engine the camshaft (rarely more than one) is part of the main engine
Pushrod engines are perceived to be "old fashioned" by the modern automotive
press, the cause is historical: While both layouts are over 100 years old, the I-head
engine came first. OHC engines were developed as more expensive high-performance
engines and have largely replaced the pushrod design in countries where cars are
taxed based on engine displacement.
The straight-4 or inline-4
is an internal combustion engine with four cylinders aligned in one row. Nicknamed
a four-banger, this straight engine configuration is the most common in cars with
a displacement up to 2.3 litres. The current "practical" limit to the
displacement of straight-4 engines in a car is around 2.7 litres. However, in tractors
and other construction machinery, four-cylinder diesel engines with a displacement
of 4.5 litres and above can still be found. The straight-4 engine is not a balanced
configuration. While a pair of pistons is always moving up at the same time as the
other pair is moving down, piston speed - as with all internal combustion engines
- is higher through the top 180 degrees of the stroke than the bottom 180 degrees,
which leads to a secondary harmonic imbalance. While this is tolerable in a small
low-displacement low-power configuration, the vibrations get worse with increasing
size and power. Most straight-4 engines below 2.0 L in displacement rely on the
damping effect of their engine mounts.
The straight-6 (also inline-6,
I-6, or I6) is an internal combustion engine with six cylinders aligned
a single row. The name slant-6
is sometimes used when the cylinders are at an angle from the vertical. Straight-6
engines have perfect primary and secondary balance and require no balance shaft.
Usually a straight-6 was used for engine displacements between about 2.5 and 4.0
L. It was also sometimes used for smaller engines but these, although very smooth
running, tended to be rather expensive to manufacture and they where inevitably
physically longer than alternative layouts.