After Blaise Pascal, French (1623-1662). The pascal, like the pund
per square inch, or the kilogram of force per square meter, is a
unit of pressure.
A type of paint that is similar to metallic paint, but instead of
minute metal particles it uses mica. Mica is a kind of semi transparent,
crystalline mineral that absorbs and reflects light in prismatic
fashion. This gives a dramatic, multi-dimensional effect to the
paint. Sometimes called "pearl coat."
A gear with a small number of teeth designed to mesh with a larger
geared wheel or a rack. Used in rack and pinion steering and the
differential ring and pinion.
The up and down movement along an imaginary axis between the front
and rear of a vehicle. Often during hard braking, the vehicle's
nose will "dive" or pitch down in front. During acceleration
the back end will "squat" or pitch down in the rear.
A partly hollow cylindrical part closed at one end, fitted to each
of the engine's cylinders and attached to the crankshaft by a connecting
rod. Each piston moves up and down in its cylinder, transmitting
power created by the exploding fuel to the crankshaft via a connecting
A gear set, generally found in automatic transmissions, in which
all of the gears are in one plane, grouped around each other like
planets around the sun. The central gear is called the "sun
The layers of cord, fiberglass, steel or structural fabric that
make up the tire carcass and reinforcing belts.
A measure of the strength of tires based upon the strength of a
single ply of designated construction. An eight-ply rating does
not necessarily mean the tire has eight plies, but rather that the
tires has the strength of eight standard plies.
Flexible, hollow rubber forming the outer part of the vehicle wheel
and inflated by air pressure.
Pound-feet measure twisting force or torque. Generated by the engine,
torque is the "push" that sets a vehicle into motion and
accelerates it. Specifications charts usually include the maximum
torque the engine can develop, and the RPM at which it is generated
(such as 345 lb.-ft. @ 3200 RPM).
A subjectively defined RPM range over which an engine delivers a
substantial portion of its peak power. The power band usually extends
from slightly below the engine's torque peak to slightly above its
A name applied to the group of components used to transmit engine
power to the driving wheels. It can consist of engine, clutch, transmission,
universal joints, drive shaft, differential gear, and axle shafts.
Powertrain components are matched according to driver needs such
as high torque, fuel economy, or convenience.
The undesirable "knock" or "ping" that occurs
when the ignition of the air-fuel mixture occurs before the ignition
spark. Also known as "pre-ignition".
A general term for any rod that transfers force in compression.
In a conventional overhead valve layout, pushrods are used to transfer
reciprocating motion from the cam followers to a more distant part
of a valve train, typically the rocker arms. Pushrods are eliminated
in overhead camshaft designs.