Termos técnicos de alguns equipamentos
The ability to avoid an accident through four distinct qualities:
excellent visibility, responsive acceleration, balanced handling and
exceptional braking. All Porsche sports cars are systematically
developed to have inherently high levels of these qualities leading to
excellent active safety.
An automatically inflating bag in front of passengers in an automobile
to protect them in the case of an accident. The airbag currently
available on U.S. versions is inflated within fractions of a second by a
gas generator located in the center of the steering wheel or in the
dashboard. The sensors which trigger the airbag respond reliably to
frontal impacts of a certain severity and angle, but not from violent
movements of the car on a bumpy road, minor collisions or if the car
is struck a heavy blow in the repair shop.
Four–wheel drive in the past has been used to improve vehicles' off–
road capabilities and/or their mobility in winter. Porsche, however, is
a leader in exploiting and refining this principle to obtain optimum
power distribution and traction under all conditions, at all times—
hence the term "all–wheel drive."
A torsion bar linking left and right wheel assemblies to create
resistance to relative motion between the two sides; limits body roll.
Also called stabilizer bar.
Literally, "breathing". When applied to an engine, refers to the system
by which air is brought into the intake manifold and distributed to the
engine’s cylinders. An engine without supercharger or turbocharger is
said to be "normally aspirated."
An engine configuration which places one or more pairs of pistons in
horizontal opposition to one another. The term may have originated
with the similarity of the piston movement to that of a boxer's gloves
moving back and forth, in a parallel plane of motion.
The extent to which a car's wheels tilt inward or outward. With positive
camber, the top of a tire tilts outward from the body; with negative
camber, the tire tilts inward.
The term Carrera, used for the first time on the 356 model, has
always indicated a model of particularly high performance and
sporting character within a Porsche Series type. The name is derived
from the famous Mexican "Carrera Panamericana" road race and has
often been applied in the past to sports racing models which were
exceptionally successful on all the world's racing circuits.
An angle describing the difference between a line drawn vertically
through a wheel's centerline and the axis around which that wheel is
A canister fitted to a car's exhaust system containing materials
designed to induce reactions resulting in a cleaner exhaust. In brief, a
catalytic converter acts as an after-burning "furnace" that consumes
exhaust gases due to catalytic combustion.
response, and the lower its fuel consumption. Four–valve engines and
twin spark plugs are two technologies working in concert with high
compression ratios to help an engine breath better, in the former, and
to more thoroughly burn the air–gas mixture, in the latter. Porsche
knock sensor technology allows the use of higher compression ratios
without damage to the engine.
A sporty two–seater with a relatively short fixed roof is known as a
coupe (from the French word for "cut off"). Whereas coupe models
always have two doors, it is possible for two additional seats to be
provided in the rear.
A driveline component designed to divide torque evenly between two
outputs capable of turning at different speeds. In all–wheel drive
systems, a central differential is often designed to divide torque
unevenly according to a predetermined ratio, such as 31/69% in the
911 Carrera 4.
The total volume displaced by all pistons of an engine as they move
from their bottom to top positions. Expressed metrically as cubic
Dual Mass Flywheel
An engine's power strokes and firing order produce crankshaft speed
fluctuations, especially at lower rpm. These, in turn, cause torsional
oscillation of the entire drive train. This is heard as rattling or
knocking of loose parts, such as gear wheels and shift elements that
are not in the power flow. Porsche's solution for this phenomenon was
development of a flywheel having additional mass after the torsional
damper, which dampens power flow oscillations entering the
Engine Management System
An automobile's computerized "brain" that monitors key engine
parameters such as rpm, coolant temperature and intake airflow via
sensors, then controls fuel metering, spark timing and other variables
according to preprogrammed "maps".
Exhaust Emission Limits
Exhaust gas is always produced when fuel is burned in an internal combustion engine. If the combustion process is not quite complete, the exhaust emissions can contain high levels of the following principal substances: carbon monoxide, oxides of nitrogen and hydrocarbons, as well as particulates. Limits are imposed to control these substances.
In 1968, California took the first action toward limiting automobile exhaust emissions. Today, almost every industrial country has introduced compulsory exhaust emission testing to ensure that only the permitted amounts of the substances are emitted by the car's engine. The fuel–air mixture supplied to the car's engine has to satisfy two conflicting needs: smooth, responsive driving with low fuel consumption on the one hand, and compliance with the exhaust emission limits on the other.
The system of passages designed to direct hot gases to escape from the exhaust ports in the cylinder head to the exhaust system.
Four–Valve Cylinder Head A cylinder head with two intake and two exhaust valves per cylinder for better engine “breathing,” particularly at higher rpm with center mounted spark plugs for ideal combustion characteristics.
A process for bonding a layer of another galvanically active metal to a sheet of iron or steel to prevent rust. The other metal (most often zinc or cadmium) sacrifices itself progressively over decades, corroding slowly so that the ferrous metal will not.
Gearbox Manual Shift
Also called "manual transmission." Porsche sports cars today feature all–synchromesh 5–speed and 6–speed manual shift gearboxes with helical–cut gears; these are notable for quiet running and light shifting action. Even reverse gear is provided with synchromesh for ease of engagement.
Horizontally Opposed Engine
More commonly known as "boxer engines" in Germany, where they have always been popular, these engines have the two banks of cylinders pointing away from each other, 180 degrees apart, and the opposed pairs of pistons move in opposite directions.
Hot Galvanizing Body Shell - A process for bonding a layer of zinc to a sheet of iron or steel, to prevent rust. This process allowed Porsche to be the first in the industry to offer a 10–year anti–corrosion warranty.
A suspension that allows each of a car's wheels to respond individually to changing road conditions, without affecting the ability of any of the other wheels to do the same.
An engine configuration in which the pistons are placed next to one another in a single line.
The system of passages designed to direct air or the airfuel mixture to the intake ports in the cylinder head.
Integrated Dry Sump
An oil reservoir contained within a Porsche engine, but separated from the whipping motions of the crankshaft. In the Boxster and 911, used in conjunction with three oil pumps and two oil swirl pots to assure a steady supply of clean, cool oil to vital engine parts.
A monitoring device that recognizes detonation in an engine and sends a signal to the control computer, which retards the timing. Use of a knock sensor permits higher compression ratios and helps protect the engine from lowgrade fuel.
A closed–loop regulating system incorporating exhaust gas measurement to ensure that the proportions of air/fuel mixture are kept constant. Measures oxygen (O2) content in the exhaust.
A channel through which an engine's gases flow. The incoming air-fuel mixture (or, with port fuel injection, air alone) is delivered by the intake manifold; the exhaust manifold removes the by products of combustion.
The industrial term for a complex assembly forged or cast as one piece. Specific to Porsche, monobloc brake calipers are complete alloy castings comprising both halves of the caliper assembly in one piece, rather than the more common method of caliper manufacture, which involves two "clamshell" caliper halves bolted together.
Perhaps the most demanding race course ever built, this course has long been a favorite Porsche proving ground. The course includes more than 17 miles of tortuous, twisting roads, over 100 curves, uphill and down and even sudden high speed "jumps" where cars become airborne over blind rises.
Fore–and–aft vertical motion of an automobile body under conditions of acceleration and road irregularities.
A pre–production, advance version of a device to allow testing and troubleshooting. Usually largely handmade since the prototype precedes the assembly line production models of the device being tested. Also may be used to refer to sports cars raced in IMSA GTP Series.
A steering mechanism in which a pinion attached to the steering shaft acts directly upon a toothed rack. Notable for its high degree of sensitivity and steering feel as well as lack of free play.
Rear Engine Layout
A major advantage of the rear–engine layout is that engine, clutch, gearbox and final drive are combined into a single compact unit. The layout offers the best available traction and acceleration under all circumstances, forward weight shift under braking, combined with light steering action resulting from the reduced front axle loads.
A special quality of all Porsches and one assured by Porsche's 10–year anti–corrosion warranty. The rigid body systems, which helps explain Porsche's standard setting precision handling.
Resistance (of tires) to the forward motion of the car as it passes over the road, caused by the tire carcass becoming deformed as each section of it has to bear the car's weight. The level of rolling resistance depends not only on the load which the tire has to bear, but also on it circumference, width, air pressure and construction, the vehicle's speed and the nature of the road surface (asphalt, snow, sand, etc.). Smaller diameter wheels, lower tire inflation pressures, and higher loads and speeds are all factors tending to increase rolling resistance.
A term summarizing all the components and assemblies on a car responsible for wheel mounting, location, suspension and braking.
A large circle of smooth pavement around which a car is driven to determine its lateral acceleration. Porsche engineers at Weissach use a skidpad to assist them in fine tuning suspension settings.
The angle between the direction a tire is pointed and the direction it is actually travelling. In cornering, tires always operate with some slip angle. The most controllable tires will exhibit a linear relationship between slip angles and cornering forces
Relative lateral movement of a tire in relation to the road surface. The greater the amount of force to be transmitted when accelerating, cornering or braking, the lower the amount of grip afforded by the road surface, and the greater the amount of slip. When a car is driving leisurely along a dry road, slip does not normally exceed 2%.
The distance traveled by the piston in its cylinder from its uppermost to lowermost position.
Sometimes called "oil sump," because this cavity at the bottom of the engine collects the oil after it drains down from its various passages ("wet sump"). The Porsche 911 Series features a "dry sump" design utilizing an oil reservoir separate from the engine proper.
A form of compressor used to pressurize the incoming air/fuel mixture for increased power. Unlike a turbocharger, a supercharger is mechanically driven, usually by a belt or chain.
Swing axle transmissions were used in the Porsche 356 Series. With this design, the drive axles were enclosed in a rigid housing that attached at the transmission differential and on the other end to the spring plate. The rigid axle housing and inner drive axle pivot (swing) at the connection joint on the transmission differential.
Dash–mounted instrument indicating engine revolutions in rpm (revolutions per minute). All Porsche models are equipped with electronic analog tachometers, mounted prominently in the center of the instrument cluster, and operating on the "pulse count" principle to provide highly accurate, instantaneous readout.
The 911 body style with removable roof panel, inspired by Porsche's racing victories in the Sicilian race through the street, the Targa Florio. Its design set a precedent for a sports car providing its owner with the structural rigidity and noise isolation of a coupe along with the open air qualities of a convertible.
The Porsche Double Function Transmission offering both automatic and manual modes. In "automatic", the transmission adapts to the driver's driving style by selecting one of five shift maps. The Tiptronic control selects a shift map while constantly measuring five variables: throttle valve opening, engine rpm, speed, lateral acceleration and longitudinal acceleration. Other unique features include a designedin reluctance to upshift before and while cornering. In the "manual" mode, the spring–loaded selector is tipped forward for upshifts and back for downshifts. Built–in safeguards prevent accidental over revving.
A suspension characteristic to counteract undesirable toe–in and toe–out. An example is the 928's widely acclaimed Weissach suspension that automatically "toes in" to offset potential oversteer under trailing throttle in a corner and/or when braking.
A slight steering of the wheels due to flexibility of the suspension bushings. In toe–in, the front of the tire points inward; toe–out is the opposite.
Thermodynamically Optimized Porsche engine
The term "TOP" has been applied to the inline four–cylinder engine used in the Porsche 968 model because of its unusually high compression ratio for a production engine, and its special combustion chamber pattern. The engine has a maintenance–free valve gear, DME engine management with electronic control of fuel injection and ignition, and is ideally equipped for a responsive flow of power, good starting and warmup, high efficiency at minimum possible fuel consumption and low exhaust emissions.
In an engine - the twisting force of an engine. Where horsepower plays a role in determining the top speed of a car, torque relates more to acceleration.
A type of fluid coupling used in automatic transmissions whereby torque is increased, although at the expense of rpm and efficiency.
Torque Tube (Central Tube)
Strong safety advantage of the transaxle Porsches — the 968 and 928 Series. The torque tube ties the front–mounted engine and rear–mounted transaxle together creating, in effect, a strong "central spine." The 911 Carrera 4 also has a torque tube connecting its rear transaxle to its front differential.
Torsional Twisting Motion - Used in four and six cylinder Porsche vehicles, torsion bars act as linear springs to suspend the weight of the vehicle. Up and down motions of the vehicle cause a twisting (torsional) force to be applied to the torsion bars. The bars behave in the same manner as a coil spring except they are straight as opposed to coiled.
A suspension element so named because it describes an arm connected to the body as its forward end and with a wheel hub at its trailing end.
A single unit combining transmission and differential. Front–wheel drive cars have transaxles, as do a very few front–engine/rear–drive models such as the Porsche 944 and 928 Series. Rear–engine cars also have a transaxle design.
Front engine/rear transmission "layout" that helps make 968 and 928 Series Porsches some of the best handling cars in the world today. The engine's weight at the front, countered by the transxale's weight at the rear, result in ideal 50/50 weight distribution. The torque tube "spine" connecting engine and transmission also has an important safety advantage—transferring impact forces at one end to the opposite end—thereby giving the occupants additional protection in an accident.
are NOT covered in TSB's.
An automobile frame consisting of rigid welded tubing.
Technology developed to increase the performance of internal combustion engines by pre–compressing the combustion air. A turbocharger is a form of compressor used to pressurize the incoming air–fuel mixture, driven by the energy of the engine's exhaust gases. The turbocharger is in two linked sections: on one side, a turbine wheel is driven by exhaust gases at speeds of up to 100,000 rpm; at the other end of a common shaft, an impeller wheel of a compressor draws air in through the air cleaner and the airflow or mass meter of the fuel injection system, compresses it and pumps it to the charge air intercooler, where it comes under the control of the throttle controlling the engine's air intake. If the exhaust gas flow is so powerful that a preset boost pressure (such as 0.7 bar) is reached, an automatic bypass valve or wastegate opens and discharges part of the exhaust gas away from the turbocharger and directly to the exhaust system, so that a constant maximum boost pressure is maintained.
Innovative turbocharging technology proven in the limited edition Porsche 959. At low rpm, all exhaust gases drive the first, smaller turbocharger only. As rpm increases and more gases are created, the second, larger turbocharger is "spooled up," gradually merging its contribution to bhp with the first, until at high rpm and greater engine output, both are fully driven.
Panel fitted to the underside of a car to help aerodynamics. The smooth panel helps avoid turbulence.
Body construction in which the car is built as one unit (monocoque) as opposed to the body being attached to a separate chassis. The body essentially acts as the car's frame.
A connection that transmits rotary motion between two shafts that lie in different planes. Some universal joints can span a large angle of difference between their input and output shafts.
The portion of a car which is not supported by its suspension. This generally includes most of the suspension itself, along with wheels, tires and brakes. Low unsprung weight permits the wheels to respond more quickly to changes in the road surface.
The device which, when open, allows gases to pass between the cylinders and the manifolds and, when closed, seals the combustion chamber. Intake valves allow the pre–combustion air/fuel "mist" to enter the cylinder head; exhaust valves allow the post–combustion exhaust gases to escape into the exhaust manifold/exhaust pipe/catalytic converter/muffler "chain."
Valve Lifter or Follower
Cylindrically shaped valvetrain component that presses against the camshaft lobe, moving up and down as the camshaft rotates.
Blanket term referring to the various parts that make the valves operate: camshafts and related drive components, parts that convert the camshaft's rotary motion into reciprocating motion at the valves, and the valves and their associated components.
A low–cost, slow–reacting way to "assign" power to the front or rear wheel of a four–wheel drive system. The input and output shafts are separated by alternately spaced thin discs turning in a cylindrical chamber filled with a viscous - meaning sticky, flow–resisting fluid. This "drag" on the discs, where the two shafts meet, causes the shafts to resist rotational speed differences.
A bleed valve that reduces excess boost pressure in the intake circuit of a turbocharged or supercharged engine. For reliable operation of the turbocharging system, a wastegate or bypass valve opens automatically when boost pressure rises too far. Part of the exhaust gas flow is then diverted away from the turbocharger and discharged directly into the catalytic converter or primary muffler unit of the exhaust system
Horizontal rotation of the car about a vertical axis passing through the car's center of gravity. A car with untamed yaw characteristics would feel as though the driver were repeatedly steering the car right and left in small jerking motions as it traveled along a straight road