Term Glossary
-----
• BRAKING •
• Braking system - The system responsible for safely slowing down and bringing a vehicle to a stop.
• ABS (aka anti-lock, anti-skid braking system) - A safety system that prevents the wheels of a vehicle from locking up or skidding uncontrollably due to extreme braking. There are various styles of ABS systems that employ techniques such as brake pulsation or manipulated engine throttle response.
• Brake Booster - A device that provides force multiplication of vacuum. The Booster transfers this force to the Brake Master Cylinder via a shaft at the end of the booster housing.
• Brake Caliper - A clamping assembly that pushes the Brake Pads against the Brake Disc Rotor. The Caliper provides the force required for the Brake Pads to slow down the rotation of the wheels through friction. There are various styles of caliper designs available including single-sided and radial types.
• Brake Disc Rotor - A metallic disc that sits on top of the Wheel Hub Assembly and behind the Rim. The rotor receives direct contact from the Brake Pads and converts the kinetic energy from the friction into heat. The Rotor absorbs the heat from this friction in order to slow down or stop the vehicle. There are various styles of rotors available including blank, drilled, and slotted types.
• Brake Fluid - A liquid that gets compressed through Brake Lines between the Master Cylinder and Caliper to provide the force needed for braking. There are various styles of brake fluid available including DOT 3, 4, and others.
• Brake Line - A line typically made of rubber, steel, or braided material that can withstand high pressure and channel Brake Fluid throughout the system.
• Brake Master Cylinder (aka BMC) - A cylinder assembly comprised of a primary and secondary piston that provides the necessary force and pressure for braking. When pushed in by the Brake Booster shaft (when the brake pedal is activated), the BMC compresses Brake Fluid through Lines leading to the Calipers, causing the Brake Pads to then clamp onto the Rotors and slow the vehicle down.
• Brake Pad - Thin metallic or ceramic blocks that clamp down and press against the Disc Rotor. The pad(s) create the friction necessary for slowing down and stopping a vehicle.
-----
• CHASSIS •
• Chassis - The framework of a vehicle’s body structure that supports and contains the drivetrain, suspension, and all other parts of the vehicle.
• Dashboard (aka dash) - The main panel inside the vehicle cabin located in the front of the interior that houses the instrument panel, climate controls, radio/infotainment system, vents, glove box, and certain parts of the electronic system. Dashboards may dry out, fade, or crack over time due to exposure to UV rays from sunlight.
• Engine Bay - The space that houses the Engine, Brake Master Cylinder, Radiator, and other critical parts. It can be located in the front (as in most vehicles), directly behind the driver (typical in 2-seater and mid-engine vehicles), or in the rear of the vehicle (as with certain modification projects and custom builds). A popular modification of the engine bay is a “tuck” (to organize and hide most exposed wires and parts) that results in a clean and tidy bay appearance.
• Fender (aka quarter panel) - A body panel that covers the front and rear wheel wells of a vehicle. Specialized fenders are popular with enthusiasts and are available in styles such as carbon fiber, widebody, and custom-molded kits.
• Firewall - The section of the Chassis that separates and isolates the Engine and Engine Bay from the interior of a vehicle. The Firewall also has fittings and points for components such as pedals and routed lines and wires. For certain applications, the firewall may have to be modified or altered in order to create clearance for certain engine swaps or custom projects.
• Hood (aka bonnet) - A panel that covers the Engine Bay. Hoods can be situated in the front, middle, or rear of the vehicle depending on where the Engine is located. Common materials of hoods include metal, carbon fiber, fiberglass, and more.
• Hood Latch - A device designed to keep the hood securely locked down to prevent a sudden release or forced opening during driving. There are various styles of latches available including specialized hood release systems and external pin kits.
• Lift Point - The ideal location for a jack or stand to safely lift and support a vehicle. This can also include points or areas from where to safely lift an engine or other heavy items. Sometimes hooks are bolted on an engine at the appropriate lift points, such as on the Toyota 2JZ-GTE.
• Lip - A thin molding at the bottom of the front or rear bumper. Lips are used for both aesthetic and aerodynamic purposes.
• Mid-Engine (aka MR, runabout, mid-ship) - A layout style in which the engine is designed to sit either in the front of the vehicle behind the front Axle, or behind the passenger compartment yet forward from the rear axle. Popular examples include the Toyota MR2, Honda NSX, and Mazda RX-7.
• Mount - A device often made of rubber and steel that allows the Engine, Transmission, or other parts to be attached securely to the Chassis. Mounts absorb roads shocks as well as vibrations produced from the engine that affect the ride handling as well as the comfort of passengers.
• Pedals - Individual levers that actuate the intake Throttle Body, Brakes, and Clutch (in manual transmission applications). Pedals are mounted at feet level and some can even be adjusted for comfort and/or performance. Some projects may require installation of a third pedal, such as in the case of installing a manual transmission in a vehicle originally equipped with an automatic transmission.
• Subframe - A separate structural device mounted to the underside of a vehicle’s framework that carries and supports vital engine and suspension components. Subframes are typically bolted or welded to the Chassis.
• VIN (aka vehicle identification number) - The identifying serial number each individual vehicle receives when built. 16-digit VINs are standard in the US, although Japanese manufacturers often use a 9-12 digit frame number with a unique serial code.
-----
• COOLING •
• Cooling system - The system responsible for regulating the operating temperature of the engine and other parts.
• Coolant (aka antifreeze, water) - A chemical mixture composed of distilled water and ethylene/propylene glycol. It is typically mixed in a 1:1 ratio (50% water, 50% glycol), although some custom or modified applications may require a unique formula. Coolant lowers the freezing point of liquid and also elevates the boiling point of water to allow for higher temperatures and pressure. Coolant also provides convective heat transfer throughout the Engine and is vital for maintaining an appropriate operating temperature. Low coolant levels can cause overheating and engine failure.
• Fan - A fan or multiple fans that blow air onto or through the Radiator in order to transfer heat to the outside air (especially during slow vehicle speeds or standing idle). Since the vehicle is not always moving quickly enough through air to transfer heat effectively, the fan(s) acts as a blower on the radiator. Fans can be installed on Radiators, Intercoolers, Differentials, and more to reduce temperature and improve performance. Fans are available in various styles including belt-driven, clutch-driven, and electronic types.
• Fan Shroud - A housing typically made of plastic, metal, or composite that optimizes cooling by channeling air flow more efficiently than the use of a Fan alone. Certain shrouds allow a fan(s) to be mounted directly on it. Common applications include use with Radiators, Intercoolers, and certain electronic devices.
• Radiator - A device with a core(s) and fins used to exchange and transfer heat. When Coolant flows through a Radiator, it exchanges some of the heat absorbed from the engine and transfers it to outside air.
• Radiator Cap - A cap that sits directly on top of the Radiator or certain reservoir/ overflow tanks. Radiator caps are calibrated to hold a specific pressure, since high temperatures result in increased pressure within the cooling system. Coolant is poured into the system through the opening in which the cap sits on. Once on securely, the cap will prevent coolant from exiting or blowing out of the Radiator due to high heat and pressure.
• Thermostat - A device that regulates Coolant flow in the Cooling System. The Thermostat typically remains closed until the Engine reaches operating temperature. Once the optimal temperature has been reached, the thermostat opens up incrementally to allow the passage of Coolant to flow through the system in order to regulate and transfer heat. The thermostat is typically activated mechanically, electronically, or by a temperature-sensitive coil-spring mechanism.
• Water Injection - A system that sprays distilled water or other liquids into the incoming air, air-fuel mixture, or directly into the Cylinder. Water injection lowers the temperature of the air-fuel mixture and reduces the potential of detonation, which then allows for higher Compression and/or Boost levels to be run safely. Injection is highly effective in both forced induction systems, as well as in aggressively timed or tuned naturally-aspirated engines.
100
• Water Pump (aka coolant pump) - A pump that circulates Coolant from the Radiator through the Engine and other cooling system components. Water pumps are typically driven by the Timing Belt or Chain in order to operate at the same speed as the engine to keep coolant flowing throughout the entire powerband.
• ELECTRICAL •
• Electronical system - The system responsible for processing electronic signals and information in order to provide desired responses.
• Air Flow Meter (aka AFM) - A sensor that measures the amount of air entering the intake system. The AFM communicates this information to the ECU in order to provide the optimal ratio of air-fuel mixture for the Engine.
• Alternator - An electrical generator attached to the Engine that converts rotational forces into electrical power. The alternator is operated by a Pulley driven by the Serpentine Belt. The electrical current produced by the alternator also charges the Battery. Alternator styles can vary in design, size, and electrical output.
• Battery - A device that supplies and stores electrical energy. The main purpose of a Battery is to start the vehicle, as the alternator takes over duties of electrical charging once the Engine is running. The alternator must then charge back the battery, as the battery discharges a percentage of its capacity during initial engine starting. Batteries are available in various styles, sizes, weights, and electrical outputs.
• Check Engine Light (aka CEL, malfunction indicator light, MIL) - A display notification on the Instrument Panel that indicates that there may be an issue within the Electronic System or some associated parts. This can originate from various sources including faulty sensors, exhaust leaks, and electronic malfunctions. CELs remain on until the issue is fixed and the Battery or ECU is reset. Most modern vehicles produce trouble codes that can be diagnosed by an OBD (on-board diagnostic) scanner that describes the issue(s) with a specific code.
• Coil - A device that transforms the lower voltage of the Battery into the thousands of volts required for the creation of spark and Ignition of the air-fuel mixture inside the Combustion Chamber. Ignition coils typically transfer electrical power to the Engine via either a Distributor, individual coil packs, coil-on-plugs, or other ignition devices
• Connector (aka plug) - A device that connects certain electrical wires to other individual wires via connector ports. This can include various multi-function wires on a single connector (common for ECU connections), linking sensors or devices to the wiring harness (such as a MAF sensor, O2 sensor, or igniter), and transferring high voltage power to the different parts of the ignition system (such as connectors for coil- on-plugs).
• Distributor - A mechanically timed ignition device that distributes electrical current to Spark Plugs that fire inside the Cylinders. An ignition coil connects to the Distributor, which then distributes electrical current between each cylinder in the proper firing order.
• Distributor Cap - A cover that houses the internals of the Distributor and insulates it from the engine and vehicle. The Distributor Cap has terminal posts that each Spark Plug wire can attach to, as well as a post for the ignition coil that supplies the large voltage needed for spark. Some manufacturers also house the ignition coil itself within the cap.
• Distributor Rotor - A rotor device that is synchronized and attached to the Distributor Shaft. The Distributor Rotor makes contact with the ignition coil via a device like a carbon brush. As the rotor spins in sync with the Camshaft, the outer edges of the rotor make contact with the terminal posts that the Spark Plug wires are attached to. This then channels electrical current to the appropriate Cylinder at the correct time.
• Distributor Shaft - A shaft driven directly by the Camshaft or a gear on the camshaft. The Distributor Rotor is attached to this shaft which provides the rotation necessary for the system to distribute electrical current.
• ECU (aka computer, engine control unit, engine control module, ECM) - A device that controls the electronic functions of a vehicle. The ECU acts like a computer, since it receives information from various sources to provide ideal responses. ECUs have become more complex throughout time and are now developed to control a wide range of actions. Although most ECUs are tuned from factory to enhance fuel economy and submit to emissions regulations, there are tuners and companies that provide custom tunes for specific applications, including for modified engines, larger turbos, upgraded fuel systems, and more. Some ECUs are also linked to a specific key unique to that vehicle and may require reflashing if lost or damaged.
• Fuses - A safety device that limits electrical current by “blowing” and opening up a circuit if too much voltage runs through it. Fuses are a common safety feature in vehicles that can prevent fires or damage caused by electrical malfunctions including power surges, faulty wiring, and over/undercharging. Fuses also complete various circuits within the electronic system and must be in good condition for the electronic system to operate properly.
• Fusebox - A housing that stores Fuses and certain Relays.
• Ground (aka negative, black wire) - The metal section of the Chassis that the negative terminal of the Battery is connected to via the negative battery cable. Additional ground wires may be installed throughout a vehicle and Engine Bay to ensure proper grounds are available to prevent shorts or other electrical issues. Ground wires may also be found directly on or around the Engine since the rubber in the engine Mounts may isolate it from grounding directly with the chassis.
• Ignition (aka spark) - The spark generated within the Engine Cylinder that ignites the air-fuel mixture and causes Combustion.
• Instrument Panel - Instrumentation that displays important measurements and controls like engine RPM speed, wheel speed, oil pressure, and other vital electronic signals like the “check engine light.”
• MAF Sensor (aka mass air flow sensor) - A device used to determine the mass flow rate of air entering the Engine. This information is provided to the ECU for proper responses to varying conditions in order to determine the ideal amount of fuel for the air-fuel mixture. Some engines may use either a MAF or MAP sensor, while some forced induction applications may even use both.
• MAP Sensor (aka manifold absolute pressure sensor) - A device used to determine air pressure in the intake manifold. This information is provided to the ECU to calculate air density and proper fuel requirements.
• Motor - A device powered by electricity to create mechanical energy. “Engines” are commonly referred to as “motors” although the two terms carry distinct meanings. Motor applications include windshield wipers, window operation, and more.
• OBD (aka on-board diagnostics) - The capability of the vehicle for self-diagnosis. If there is an issue with a certain system, sensors will recognize this and send a signal in the form of a “check engine light”. Some applications will allow for a specialized computer to plug into its OBD port (OBD2 and newer), while others (typically older) may require contact through wires on a port to trigger a diagnostic mode that can produce the trouble codes. There are various styles of OBD systems, including OBD0 (up until around 1991), OBD1 (around 1992 to 1995), OBD2 (around 1996+), and others.
• Relay (aka switch) - A switch that operates and controls a circuit using a low-power signal. There are various styles of relays available that are responsible for operating circuits like headlamps and other lower-voltage components. Instead of electrical power traveling directly from the battery to the headlamp, which would require a heavy-duty switch due to the high voltage, it first travels to a specific relay responsible for that operation. Inside the relay will typically be an electromagnet, in which only a small amount of power is needed from the switch (in this case, it is the headlight switch on the steering column shaft or dashboard that is activated for the lights to turn on) to complete the circuit by activation of a solenoid (commonly heard as a “click”). Power can then travel directly from the battery to the headlamp without overheating and frying the wires or other electronics in the system.
• Solenoid - A small coil typically designed in a cylinder-like shape that is actuated electronically or hydraulically to engage or make contact with another part. There are various styles and purposes of solenoids, including those that work with relays, starters, variable valve timing mechanisms, and automatic transmissions.
• Spark Plug - A device that facilitates Ignition and spark in the Combustion Chamber. When electrical power travels from the ignition system and through the Spark Plug, the current must jump a small gap at the bottom end of the plug in order to complete its circuit. This jump creates the spark that ignites the air-fuel mixture in the Cylinder during the power cycle when the Piston is approaching “TDC” (top dead center). Engines typically have a specific spark plug application that may vary in length, material, gap size, and temperature range.
• Starter - A device that locks onto the teeth of the outside edge of the Torque Converter (for automatic transmission applications) or Flywheel (for manual transmission applications) and turns it over to allow the Engine to start and run under its own power. Since the current needed to operate the starter is so great, the battery must have an adequate voltage or else the starter will not operate or engage.
• Throttle Position Sensor (aka TPS) - A sensor that determines the exact position and angle of the Throttle Body. The ECU uses this information to adjust for fuel delivery and other tasks.
• Traction Control (aka TRC, TC) - A safety mechanism that helps the vehicle counter a loss of traction by making adjustments electronically and mechanically. There are various styles of traction control systems including some that adjust the throttle body to limit air intake and others that send power to wheels with the most traction. These systems vary by manufacturer and can sometimes be turned off by a button or switch.
• Wiring Harness - An organized group of wires that includes connectors and terminals that allow the ECU to receive information from sensors and other electronics. Some vehicles may have separate harnesses for the Engine, Transmission, and Dashboard electronics. There are also specialized wiring harnesses available for unique applications from aftermarket manufacturers.
-----
• ENGINE •
• Engine - A mechanical device that converts reciprocating motion into rotational torque.
• Airbox - A box housing that channels air into the intake system and holds the air filter in place.
• Air Filter (aka air cleaner) - A device typically made of fibers, cloth, or paper that prevents particulates in the air like dust and other matter that may damage engine internals from entering the Intake Manifold and Engine. Air Filters are usually housed in an airbox or as a stand-alone cone-type filter. Both Fuel-Injected and Carbureted engines use air filters as well as Forced Induction systems.
• Backfire - An event in which Combustion occurs outside the Engine, such as in the Intake or Exhaust system. This can be the result of unburned fuel igniting inside the exhaust system, called after-fire, or fire being taken in by the intake system. Causes include rich fuel levels and poor ignition. This can result in damaged exhaust system parts which lead to exhaust leaks and fouling of the Catalytic Converter, which can greatly reduce performance by restricting exhaust flow.
• Blow-by - An event in which either the air-fuel mixture blows down into the Crankcase through the Piston Rings, or oil from the crankcase blows up past the piston rings into the Combustion Chamber and mixing with the air-fuel mixture (producing a blue-ish smoke when ignited). This creates a loss of engine power as cylinder Compression is reduced as well as possible fouling of the engine oil with harsh chemicals present in the air-fuel mixture that alters the chemical balance of the oil that must lubricate critical internal engine parts.
• Camshaft (aka cam) - A shaft with lobes that operates the Valves in the Cylinder Head of an OHC (overhead cam) engine. Cam lobes are designed with specific angles and degrees for exact “lift” and “duration” characteristics. This commands how much air- fuel mixture can enter and exit the engine Combustion Chamber and for how long the valves remain open and closed. A Cam is often driven by the Timing Belt or Chain and is synchronized with the Crankshaft to ensure proper timing throughout engine cycles.
• Combustion Chamber - The space within the Cylinder where spark and combustion occur. The Cylinder Head, Valve stem discs, and Spark Plug form the top area, while the Cylinder, Piston crown, and Rings make up the rest of the combustion chamber.
• Compression (aka cylinder pressure) - A value of the ratio of volume a Combustion Chamber can hold. It reveals the state and condition of the Piston, Rings, Valves, seats, and Cylinder Head Gasket. Each of the cylinders’ compression measurements are recommended to be within 15% of other cylinder results in order to qualify as a healthy-wearing engine. Manufacturers suggest a typical range indicating the ideal compression results for each engine. The ideal compression ratio (typically measured in PSI or kg/cm^2) will vary between engine designs and be based on unique characteristics including engine displacement, head design, and forced induction application.
• Connecting Rod (aka rod, conrod) - A device that connects a Piston and its movement relative to the Crankshaft. The Connecting Rod converts the reciprocating “up and down” motion of the piston into rotational movement of the crankshaft, known as torque. The piston will both push and pull on the connecting rod during engine cycles and rotate the crankshaft of the engine.
• Crank Sensor - A sensor that monitors the position and RPM of the Crankshaft. This information is given to the ECU for adjustments to ignition timing. If the crank sensor malfunctions or recognizes something irregular with the position of the crankshaft, the engine may cut out (turn off) or not start as a precaution.
• Crankshaft (aka crank) - A mechanical crank device able to convert reciprocating motion into rotating force. The Crankshaft rotates inside of an enclosure lined with Bearings. The forces produced by the Piston and Connecting Rod turn the crankshaft over. Lack of oil maintenance can cause crankshaft lockup or complete failure. Crankshafts are made of various materials and can be cast or forged for higher tensile strength. Output of the crank is measured in torque and can be converted to horsepower.
• Cylinder - a hollow space with a circular cross section in which the Piston travels up and down in.
• Cylinder Head (aka head) - A machined assembly that contains the Valves, Cams, Fuel Injectors, Spark Plugs, and Intake/Exhaust ports. The head is located directly above the Cylinder and also forms the top area of the Combustion Chamber.
• Dipstick - A thin measuring device equipped with a handle that reads whether there is enough fluid in a particular system. Most dipsticks will not measure an exact volume amount but instead a level between full (F) and low (L). Dipsticks will also display the progression of any fluid loss due to leaks, burning, or underfilling. There are various styles of dipsticks that are used in Engines, Transmissions, Power Steering systems, and more.
• DOHC (aka dual overhead cam) - A style of Cylinder Head that uses two individual camshafts to operate the intake and exhaust Valves separately.
• Cylinder Head Gasket (aka head gasket) - A critical gasket that sits between the Cylinder Head and the top of the Cylinder base. This gasket is crucial for engine performance and holding Compression. Symptoms of Head Gasket failure can include engine overheating and loss of compression. Faulty head gaskets can also cause a mix of oil and coolant that resembles chocolate milk and can be evident in the radiator, overflow tank, or exhaust. For high performance applications, stronger and denser metal head gaskets may be introduced to provide greater durability.
• Idle - The speed of the Engine while a vehicle is motionless and the accelerator (gas) pedal is not being pressed. There are general ranges for an ideal idle RPM that will vary by engine style or application.
• Idler Pulley (aka tensioner pulley) - A pulley responsible for guiding or applying tension to the Serpentine or Timing Belt. Idler Pulleys are often adjustable in order to provide the proper tension.
• Idle Air Control Valve (aka IAC, IAC valve) - A device that regulates Engine RPM at Idle. It is often controlled by the ECU and can manipulate and flutter the Throttle Body at idle. This will adjust the amount of air taken into the engine while the gas pedal is not being pressed on.
• Intake Manifold - A device that captures and distributes air to individual Cylinders. The Intake Manifold sits between the Throttle Body and the Intake Ports on the Cylinder head. Certain parts like fuel injectors, electronic sensors, and vacuum ports may be built into or installed on the intake manifold.
• Intake Ports - Channels in which air from the Intake Manifold enter the Engine.
• Main Bearings - The bearings that the Crankshaft rests upon that prevents dislodging due to forces created by the Engine. It also allows for smooth rotation of the crankshaft. Main bearings are typically available in plain or journal types and can vary by manufacturer.
• Piston - A crown-shaped device attached to one end of a Connecting Rod that moves up and down a Cylinder. It is responsible for vacuuming in air, compressing air-fuel mixture, forcing the connecting rod down, and pushing exhaust out from within the cylinder. Different pistons can be used to modify an Engine’s Compression ratio.
• Piston Ring - Flexible rings located in grooves around the edge of the Piston that can expand to hold Compression (compression rings) or distribute oil (oil rings). Faulty rings can cause blow-by, cylinder scoring, oil burning, and engine failure.
• Pre-Detonation (aka engine knock, pinging) - An event in which either combustion of the air-fuel mixture is not properly synchronized with the timing system, the air-fuel mixture is prematurely detonating due to low octane levels in the fuel and igniting prior to spark due to high cylinder temperatures, or the Engine is experiencing overloads of pressure from a Forced Induction system. This can lead to terminal engine failure if unaddressed.
• Pulley - A round wheel with grooves around its edge meant for a belt. Parts like Alternators and Power Steering Pumps typically use some form of Pulley. Pulleys are available in various sizes, materials, colors, and applications.
• Rod Bearing - A bearing at the large end of the Connecting Rod that attaches to the Crankshaft. This bearing allows for smooth movement and rotation of the crankshaft relative to the motion of the Piston and rod.
• SOHC (aka single overhead cam) - A style of Cylinder Head that uses only one Camshaft to operate both intake and exhaust Valves.
• Serpentine Belt (aka v-belt, accessory belt) - A closed continuous belt that drives the Pulleys of external device accessories such as the Alternator, Power Steering Pump and A/C compressor. The belt is kept tight by an Idler Pulley or tensioner that keeps the belt properly tensioned and going in the correct loop.
• Tensioner - A device that maintains tension against the Timing Belt or Chain. Tensioners help prevent the jumping of timing of the Engine by eliminating any slack on the timing belt or chain. There are various styles of tensioners including fixed, hydraulic, and spring-loaded types.
• Throttle Body (aka butterfly) - A butterfly (fluttering) valve that regulates the amount of air entering the Engine. The Throttle Body sits between the air intake tube and the Intake Manifold. Styles include drive-by-cable (a system that is mechanically linked to the accelerator pedal via a cable) and drive-by-wire (sensors determine how much to open or close the throttle body relative to the angle the accelerator pedal is being pressed on by the driver’s foot).
• Timing Belt (aka cam belt, water pump belt, crank belt) - A toothed belt that synchronizes timing and rotation of the Camshaft, Crankshaft, and Water Pump. This allows the intake and exhaust Valves to open and close at the correct times relative to the position of the crank. Proper timing of the belt ensures the Piston(s) is at the proper degree angle during its cycle. Water pumps are also driven by the timing belt and will rotate at the same speed as the engine. Timing belt failure can cause severe issues, especially in interference-type engines where valves have the potential to clash with the piston.
108
• Timing Chain - A roller chain that performs similar functions to that of a Timing Belt. Differences include: 1. the Timing Chain is generally internal, meaning it is not openly accessible like a belt is, 2. it usually rides on a guide that keeps it in place and in-line with its designed route, 3. unlike a timing belt’s common use of an Idler Pulley, a timing chain typically has a tensioner device that holds the chain or guide firmly in place to prevent jumping or skipping of timing, and 4. instead of having toothed features that grab onto gears like a timing belt, the chain uses rollers to lock onto sprockets attached to the Cam, Crankshaft, and other timing components.
• Timing Cover - A cover that insulates timing components from outside elements. Components like the Timing Belt/Chain and Water Pump are typically found under this cover. Some timing covers also have engine mounting points built right onto it.
• Valves (aka engine valves, valvetrain) - Stem-like devices that sit in the intake and exhaust ports of the engine that open and close in synchronization with the Cam and Crankshaft. Valves allow air in and exhaust gases out of the Engine. When a valve is closed, no air or exhaust gas should be able to enter or exit any port. This is vital for maintaining an ideal Compression ratio in the Combustion Chamber. When an intake valve is opened by its assigned camshaft lobe and in accordance with timing, air-fuel mixture will flow into the combustion chamber. When an exhaust valve is activated by the camshaft, it allows exhaust gases to exit the chamber and will then close fully right before the intake cycle begins again.
• Valve Cover - A device made of metal or composite that covers the Engine Camshaft(s) and Valves. This cover also has ports for Spark Plug access and fittings for vacuum and breather lines. A valve cover may require a gasket or RTV on its outer edge and around the spark plug ports to prevent oil leaks.
• Variable Valve Timing (aka VVT-i, VTEC, VVL, MIVEC, AVLS) - A mechanism that adjusts the timing and specifications of valve lift events. Benefits of this feature include enhanced fuel economy and optimal performance throughout the powerband.
-----
• EXHAUST •
• Exhaust system - The system responsible for expelling engine exhaust gases efficiently.
• Catalytic Converter (aka cat) - A device responsible for converting exhaust gases into less toxic emissions via a redox reaction (reduction and oxidation). This component is necessary in order to pass certain inspection and emissions tests required in certain states or areas. Catalytic Converters are typically located shortly after the Exhaust Manifold or Header and are typically covered with a heat shield due to the high temperatures produced by the converter.
• Down Pipe (aka test pipe) - A pipe that sits between either the Exhaust Manifold, Header, or Turbocharger and the rest of the exhaust system. There are various styles of downpipes available in unique sizes, designs, and materials.
• Emissions (aka exhaust gases, exhaust fumes, CO2) - Gases and particles emitted from the exhaust system. Emissions are regulated federally in the US (as well as further regulated by individual states like California) and require certain equipment parts, including an unmodified catalytic converter and factory exhaust system in order to pass inspection.
• Exhaust Manifold - A casting that collects Exhaust Gases being released from the Engine after ignition and combustion.
• Flex Pipe - A flexible pipe along the exhaust system that allows for some play or movement in case of rough shocks or vibrations while driving.
• Header - A tubular Exhaust Manifold. Headers typically have one tube per individual exhaust port that eventually meet other tubular pipes soon after. There are header combinations like 4-2-1, 6-3-2-1, and many others depending on the specific engine layout and application.
• Muffler (aka tail pipe) - A device designed to muffle (lower) the amount of noise emitted by the exhaust system. Mufflers are typically located at the tail end of a vehicle to allow for the exit of Exhaust Gases. There are various styles of aftermarket models available including some tuned to maximize sound and rumble.
• Oxygen Sensor (aka O2 sensor) - A sensor mounted in, on, or around the exhaust manifold or Catalytic Converter that monitors how much unburned oxygen the Engine emits. This sensor determines if the engine is running at ideal, lean, or rich fuel levels and may trigger a “check engine light” if there is an issue.
-----
• FORCED INDUCTION •
• Forced Induction system - The system responsible for delivering dense, compressed air into the engine via a turbo, supercharger, or other forced induction device.
110
• Boost - A term that describes the air pressure in the inlet manifold of a forced induction system and is often measured in bars, PSI (pounds per square inch), or simply as “pounds”.
• Blow-Off Valve (aka BOV, compressor bypass valve, CBV) - A relief valve in a Forced Induction System designed to release pressurized air when the throttle is lifted or closed. Compressor bypass valves (a form of relief valve/BOV) will recirculate this air into the non-pressurized end of the intake system between the MAF sensor and the Turbo air intake. This in contrast to a typical blow-off valve, which instead of recirculating like the CBV will actually instead release excess pressure directly into the atmosphere that results in a unique whistle sound.
• Charge Pipe (aka intercooler piping) - A pipe that feeds compressed air in and out of an Intercooler. The compressed air from the Turbo or Supercharger will enter the intercooler via a Charge Pipe. The air exiting the intercooler and heading towards the Engine also travels through an individual charge pipe.
• Flange - A device that sits between and connects the turbo (exhaust) manifold to the turbocharger. A gasket typically sits between the flange and manifold as well as between the turbo in order prevent leaks between the union of the parts. Flanges are available in various materials, sizes, and designs.
• Intercooler (aka I/C, TMIC, SMIC, FMIC) - A device that cools the air that is introduced and compressed by a Forced Induction System. Air taken in by a Turbo or Supercharger becomes very hot as a result of passing through the compressor and housing. The Intercooler cools off the internal contents (hot, compressed air) by passing it through moving air like a Radiator. By lowering the temperature of the compressed air (which increases density), more oxygen for stronger combustion and power potential can be provided. Intercoolers are available in various styles including top-mount, side- mount, front-mount, and water-injected types.
• Nitrous (aka NOS, juice, spray) - A chemical gas injected into the fuel system, intake system, or Cylinder Head that drastically reduces air temperature and increases density. This greatly improves the volumetric efficiency of the Cylinder and results in large horsepower gains in short bursts (only while the nitrous is being released into the system). Too much use of nitrous will have catastrophic effects on an Engine that is not specifically built for high performance.
• Supercharger (aka blower) - A Forced Induction System component that utilizes a mechanically driven compressor to increase the intake and compression of air delivered into the engine. This increase in oxygen allows for more fuel to be mixed with the higher volume of air introduced in order to create more powerful combustion, leading to large performance gains. There are various types of Supercharger system styles available including roots, sliding vane, and centrifugal types. Unlike a Turbocharger, a supercharger is typically driven by a belt, direct drive, gear drive, or chain drive and is powered directly by the engine.
• Turbo Manifold - A manifold device that efficiently collects and routes exhaust gases from the Engine. These gases then flow through the flange and into the turbine of the Turbocharger. There are various styles of turbo manifolds available for specific engine and horsepower applications.
• Turbocharger (aka turbo, snail) - A Forced Induction System component that routes expelled Exhaust Gases through a turbine wheel before allowing the exhaust to exit the system. This turbine propellor wheel is attached to a shaft that is also connected to a compressor wheel on its other end. This air compressor takes in a much larger volume of air than a naturally aspirated system can and has a greater potential for performance gains when paired with the proper fuel system and tune. Turbos are available in various sizes, applications, compressor/turbine specifications, and horsepower capabilities.
• Wastegate - A valve in the Turbo Manifold that redirects Exhaust Gases originally intended for the turbo and instead channels it towards the downpipe or atmosphere. This prevents the turbocharger or Supercharger from surging and allows for tuned boost limits. There are both internal and external Wastegate styles available and can vary in size, design, and boost pressure limits.
-----
• FUEL •
• Fuel system - The system responsible for providing fuel for the air-fuel mixture required for internal combustion in an engine.
• Fuel (aka gas, gasoline, diesel) - A material that produces heat and power when ignited. When gasoline or diesel fuel is mixed with air in a certain ratio, an ideal combustible air-fuel mixture is produced for use in the Combustion Chamber. This explosion will force the Piston down and is a vital step in the four-stroke power cycle. Engine ECUs are typically tuned for use with a specific fuel octane level, such as 89, 93, etc., in order to prevent issues like Pre-Detonation.
• Fuel Filter - A filter in the Fuel Lines that screen out dirt or particulate contaminants.
• Fuel Injector - A device that sprays liquid fuel into the Intake Manifold or directly into the Cylinder (direct injection) in order to mix with air to create an air-fuel mixture for combustion. Fuel Injectors are signaled by the ECU to open (releasing pressure) and spray for a specific amount of time. Pulse width is measured by how long an injector stays open, determining the amount of fuel delivered during its cycle. The injector is set to open at just the right time in order to coincide with the intake stroke of the engine cycle. Larger volume injectors may be necessary for high horsepower or Forced Induction System applications in order to keep up with fuel demands imposed by introducing larger amounts of air. Injector size and capability is usually measured in CC (cubic centimeter), or the volume of fuel it displaces.
• Fuel Lines - Lines that transport fuel from the fuel pump through the system.
• Fuel Pump - A device designed to create a pressurized system to carry Fuel from the Fuel Tank through the Lines leading to the Engine. In certain high horsepower applications where much fuel is needed, a larger capacity Fuel Pump may be necessary to provide adequate amounts of fuel.
• Fuel Rail - A device that supplies and distributes Fuel to the Injectors for delivery into individual Cylinders.
• Fuel Pressure Regulator (aka FPR) - A regulator device that maintains the ideal or desired fuel pressure for the Rail and Injectors. In certain scenarios, an FPR will display the PSI pressure through a wet gauge and may offer features for adjustment.
• Fuel Tank - A container that stores Fuel and often houses the Fuel Pump.
• Lean - A running condition referring to excessive amounts of air or not enough fuel in the air-fuel mixture. Lean conditions can be caused by ECU malfunctions, problematic tuning, or fuel system issues. Running lean causes higher-than-normal temperatures in the Cylinder(s) and can be detrimental to the health and longevity of the Engine.
• Rich - A running condition referring to excessive amounts of fuel or not enough air in the air-fuel mixture. Rich conditions can be caused by ECU malfunctions, problematic tuning, or intake and ignition system issues. Running rich causes fouling of the Spark Plugs (which leads to ignition issues and bad performance), carbon deposits in the engine and intake & exhaust ports, and clogging of the Catalytic Converter (exhaust restriction). Richness issues can be detrimental to the health and longevity of the Engine.
-----
• MISCELLANEOUS •
• Miscellaneous parts - A term that refers to general parts, as well as fasteners like bolts, screws, nuts, tools, and other loose parts.
• Bearings (aka race) - A device that limits relative motion to only the desired motion while also reducing friction between moving parts like rotating shafts. There are various applications for bearings, including use in wheel hub assemblies and crankshaft ends.
• Bracket - A device designed to hold, support, and align parts. Brackets are typically used to support the Alternator, Exhaust Manifold, license plate, and various other applications.
• Gasket (aka seal) - A device used to prevent oil or air from seeping in or leaking out a system or part, such as the Valve Cover, Oil Pan, Throttle Body, and Intake Manifold.
• Gear - A toothed wheel that meshes with, drives, or is driven by another gear or belt. Common applications include use with Camshaft ends, Engine Timing components, Transmissions, and Differentials. Gears are designed in many styles including spur, helical, and bevel types.
• Jack (aka lift) - A device for lifting vehicles, engines, and other heavy items. There are various styles of jacks available including mechanical and hydraulic types.
• Jack Stand (aka stand) - A stand device that keeps the vehicle, engine, or item propped up once it has been lifted to ensure safety in case the jack fails.
• Pallet (aka skid) - A common shipping device that is flat, typically made of wood, and easily lifted by a jack or forks. Pallets are a common packaging tool for shipping engines and large parts due to their durability and relatively low cost.
• Sprocket - A toothed wheel designed to drive perforated links such as those on a chain. There are various styles of sprockets available that include use with Timing Components in Engines equipped with Timing Chains.
-----
• OIL •
• Oil system - The system responsible for providing optimal lubrication and cooling in areas where metal-to-metal contact occurs in the engine.
• Oil - A complex lubricant that protects the Engine from internal wear, energy loss, and lock-up. There are various types of oil including conventional, semi-synthetic, and synthetic, as well as different weights and formula compounds that vary by manufacturer, producer, and application.
• Oil Cooler - An external device that cools Oil by passing it through the air, similar to how a Radiator or Intercooler cools their contents.
• Oil Filter - A device used to filter out particulates in the Oil System.
• Oil Pan (aka sump) - A device that contains and stores Oil for the Engine. Oil Pans are designed to accommodate critical parts like the Oil Pick-up Tube, Dipstick, baffles, and more. There are certain engines, such as the Toyota 2JZ-GTE, that may use different oil sump designs (front Aristo or rear Supra types) for specific vehicle models in order to fit and clear certain parts like the crossmember or steering components that would have otherwise interfered with the oil pan.
• Oil Pick-up Tube - A short pipe with a mesh strainer that extends to the bottom of the Oil Pan to retrieve Oil for the Oil Pump.
• Oil Pump - A pump that circulates Oil under pressure to Bearings, Pistons, Camshafts, and other rotating or contact-prone parts.
-----
• STEERING •
• Steering system - The system responsible for how the vehicle steers and turns.
• Power Steering Pump (aka P.S. pump) - A hydraulic pump that reduces the effort it takes to turn the wheels, especially at slow or idle Engine speeds.
• Rack and Pinion (aka steering rack) - A gearset that converts rotational motion into linear motion. The Pinion (a circular gear) meshes and engages with teeth on the Rack (a linear gear) in order to move the front wheels from left to right. The Steering Wheel dictates the movement and control of this motion.
• Steering Column - A device that connects the Steering Wheel to other components of the Steering System. Certain controls are often installed on the column, including switches for the headlight, turn signal, and windshield wiper features on certain vehicles.
• Steering Hub - A device that certain Steering Wheels are attached to. Specialized hubs may be required for certain applications, including removable steering wheels.
• Steering Wheel - A device typically shaped and designed as a sphere or circle that controls the direction and travel of the front wheels of the vehicle. All steering system components respond to the input of the steering wheel. Steering wheels are available in various styles, colors, materials, and electronic capabilities.
-----
• SUSPENSION •
• Suspension system - The system responsible for absorbing and controlling shocks, movements, and overall handling of the vehicle.
• Bushings - Cushions made of materials such as rubber or polyurethane that are mounted on suspension and steering joints to absorb shock and noise from the road. These bushings also control the amount of movement allowed between these joints (known as play). Movement and play can increase as Bushings wear out. There are various styles of bushings available for a wide range of high performance and comfortability applications.
• Camber - The angle of the wheels on a vertical axis. If looking directly at the front of the vehicle and the bottom of the wheels stick further outward, this is referred to as negative camber. If the opposite occurs and the top of the wheels stick further outward, this is referred to as positive camber. Camber is measured in degrees and can be adjusted for a wide range of applications.
• Coilover (aka coil over shock, spring over shock) - A single unit device that consists of a spring that coils around and encircles a shock. Certain coilover systems allow for adjustment of dampening, ride height, and preload settings. There are various styles of coilovers available, including full, slip-on, and “spec racing” systems.
• Control Arms (aka UCA, LCA) - A linking device that connects the Chassis to the Suspension System and Wheel Hubs through Bushings and other heavy duty hardware. The interior end of a Control Arm (pointed inwards towards the center of the chassis) houses a bushing that isolates vibrations and dampens energy passing through it. The exterior end (pointed outwards towards the wheel) maintains a radial distance and allows for only one degree of movement freedom. Upper and lower control arms are unique and perform respective tasks.
• Lug Pattern - The amount of studs on a wheel hub and the distance between them if an imaginary circle was drawn around them. Patterns are usually marked in this order: 5x114.3” would be measured as 5 studs on the hub that measure a diameter or 114.3” around all 5 lugs. Manufacturers have developed various lug patterns throughout the years depending on the application of the vehicle, such as that of heavy duty towing, economic city travel, and high performance racing.
• Rims - A rigid, circular device in which the tire is mounted on. Rims are mounted directly on the Rotor and Wheel Hub assembly and are available in various colors, spoke patterns, lug patterns, styles, sizes, weights, materials, and processes (such as cast or forged).
• Shocks (aka shock absorber, damper) - A mechanical or hydraulic suspension device that controls the amount of bounce created by the rebound of the Spring when absorbing bumps. The Shock converts the kinetic energy of the rebound into heat. Shocks are an essential part of the Suspension System and significantly affect vehicle handling and ride quality.
• Spring (aka coil spring) - A torsional suspension device that can store and release energy. A Apring maintains a specific force between two contacting surfaces and also determines the ride height of the vehicle. As a wheel drives over a bump, the spring will compress (store energy) and then rebound (release energy) to its original position.
• Strut Tower - The base that the top of the suspension (coilover, strut, etc.) is bolted onto. Strut Towers are located on both sides of the engine bay as well as in the rear of some vehicles. Towers are typically reinforced for rigidity and strength. Implementation of a strut tower brace (a bar that bolts onto both strut towers) will result in less torsional flex of the chassis during aggressive driving.
• Sway Bar (aka anti-roll, anti-sway, stabilizer bar) - A device that minimizes vehicle body roll during aggressive cornering or turning. The Sway Bar will extend to both sides of the Axle (wheel to wheel) and is connected to the Chassis/Suspension through the Sway Bar End Links.
• Sway Bar End Link - A device located between the end of the Sway Bar and one side of the vehicle Axle that transfers force through the sway bar. The energy spreads through and travels from the Suspension of one side of the axle and end link through the sway bar and onto the opposite side suspension and end link.
• Tire (aka tyre) - A circular device made of rubber and other compounds that grip onto the outer edge of a rim and provides traction as it makes contact with the road. When the Tire and Rim are together as one unit, this is commonly referred to as a complete wheel. There are various tire styles, applications, treads, compounds, and sizes available.
• Toe (aka track) - The angle of the front wheels in relation to the longitudinal (horizontal, left to right) axis of the vehicle. If looking directly at the front of the vehicle and the front part of the front wheels are angled further inward (pointing toward the the center of the vehicle), this is known as “toe in”. If the opposite occurs and the front of both wheels are facing slightly outward (pointed away from the center of the vehicle), this is can be measured as “toe out”.
• Tread - The section of tire that channels water and other debris away from road contact points. Treads are designed for various applications including drag racing, off- road, and fuel economy.
• Wheel Hub Assembly (aka hub) - A device that houses Bearings that allow for smooth rotation of the wheels. The Hub assembly sits between the Brake Disc Rotor/drum and the Axle itself. Some suspension components like the bottom of the Shock may be bolted to the wheel hub assembly of certain vehicles. The hub also houses the studs used when mounting and tightening wheels.
• Wheel Alignment - Adjustment of the unique wheel angles of a vehicle to a specific measurement range including adjustment of Camber, Toe, and more. The purpose of an alignment is to provide the desired steering input from the driver and for the vehicle to drive as straight as possible without veering from side to side. Certain driving applications such as off-road, stance, and drag racing may adjust for unique measurements in their respective alignment.
-----
• TRANSMISSION •
• Transmission system - The system responsible for converting engine torque into power for the wheels.
• All Wheel Drive (aka AWD) - A transmission delivery system that powers all four wheels at all times. Example systems include symmetrical AWD by Subaru, ATTESA (Advanced Total Traction Engineering System for All-Terrain) by Nissan, and All-Trac/ GT-Four by Toyota.
• Axle (aka half shaft, CV joint) - Shafts that connect the wheels to the Trans-Axle or traditional Differential unit. The Axle transfers power from the differential and delivers it to the wheels. An axle can both refer to an individual half shaft, as well as the axis of the wheels being driven (front and rear axle, passenger side front axle, FWD, RWD, etc.). Axles are sometimes referred to as half shafts because two are required to make one complete axle. In certain applications, both half shafts may seem alike, while others may have noticeable size, design, length, and performance characteristics.
• Clutch - A device attached to the Flywheel in a manual transmission application. It is responsible for incrementally engaging and disengaging the transfer of torque from the Engine to the input shaft of the transmission through a series of discs or plates. Clutches are available in various styles including single-disc, multi-disc, and dry-clutch types.
• Differential (aka diff, pumpkin, rear, rear end) - A gear train component of the transmission system designed to compensate for the difference in distance that the inner wheel travels as opposed to the outer wheel when the vehicle turns or goes around a corner. Differentials for RWD vehicles are typically housed separately on the rear axle and use a heavy weight oil for lubrication. In FWD applications, the differential is built into the transmission as one unit, forming what is known as a “Trans-Axle”. There are various styles of differential output systems including open and various limited-slip (LSD) types.
• Driveshaft - A device that connects to the transmission output shaft and transfers power to an external differential. Driveshafts are typical in RWD and certain AWD/4WD vehicles and are available in various materials, weights, and styles (such as one- or two-piece).
• Flex Plate (aka automatic flywheel) - A rotating disc bolted to the Engine Crank (near its center) that the Torque Converter also bolts on to (on its outer edge). The Flex Plate allows the Torque Converter to match the engine speed. Flex plates are exclusive to automatic transmission systems.
• Flywheel - A rotating disc bolted to the Engine Crank (near its center) that the Clutch is also bolted on to (on its outer edge). The Flywheel allows the clutch to match the engine speed and enhances momentum and stability of the rotational power of the engine (torque). Flywheels are exclusive to manual transmission system applications and are available in various styles, weights, and materials.
• Four Wheel Drive (aka 4WD) - A transmission delivery system that powers all four wheels either full-time or part-time, and can also switch from high and low gears. Examples include common truck, off-road, and utility applications.
• Front Wheel Drive (aka FWD) - A transmission delivery system that powers only the front wheels at all times.
• Half Shaft (aka CV joints) - A Driveshaft that connects the Trans-Axle or traditional Differential unit to the wheels. It is referred to as half because two are required to complete one full Axle. In certain applications, both half shafts may seem alike, while others may have noticeable design, size, and performance characteristics.
• Limited Slip Differential (aka LSD) - A device that allows for different speeds of the wheels but limits the maximum difference between them, hence “limiting slip.” There are various styles of LSD available including viscous, geared, welded, clutch, 2-way, 1-way, 1.5-way types, and more.
• Rear Wheel Drive (aka RWD) - A transmission delivery system that powers only the rear wheels at all times.
• Shifter - A mechanism attached to the shifting assembly or gear selector of the transmission. In manual transmission applications, the shifter is used to engage and switch gears manually. In automatic transmission applications, the shifter selects what gear to operate, such as P (park), R (reverse), N (neutral), and D (drive). Shifters typically sit in the center console, but there are examples of some located on the dashboard or steering column. Shifters are available in various lengths, styles, and materials.
• Shifter Knob - A weighted device at the top end of the shifter handle/lever that the driver grips while changing gears on the transmission.
• Torque Converter - A circular coupler device that transfers torque from the Engine to the automatic transmission. The Torque Converter is able to multiply torque (especially at low engine speeds) to allow a smooth initial take-off of a vehicle. The torque converter sits between the Flex Plate and the transmission input shaft. There are various styles of torque converters that vary in application, design, and weight.
• Trans-Axle - A device that houses both the transmission and differential in one unit. This system is common in many FWD applications.
• Transmission Fluid - A specialized liquid that lubricates gears and other moving parts inside the transmission and Torque Converter. Fluid types vary by application, weight, and formula compound.
-----
• TERMS •
• Terms - An expression or phrase used to describe a certain concept or event.
• ASE Certification (aka Automotive Service Excellence certification) - A certification awarded by a special group that certifies professional technicians and shops in the automotive repair industry. There are nine different Automobile & Light Truck Certifications (A1 through A9).
• Bill of Sale - A contract that is written and agreed upon by both buying and selling parties that notes particular details of the exchange including price, item description, full buyer and seller names, drivers’ license numbers, mileage, and other important aspects of the sale. This creates a historical document of the sale and can also be officially notarized for use in legal procedures.
• Block - A term that refers to an engine or may also refer to subcategories like short block or long block. Short block refers to only the bottom end of an Engine or Crankcase. Long block refers to an entire engine block assembly including the bottom end, Cylinders, and Cylinder head together as a complete unit.
• Bottom Dead Center (aka BDC) - The position of the crank when a specific Piston is at its nearest point to the Crankshaft in terms of distance.
• Corrosion (aka rust, pitting) - The surface of metal or other materials when it rusts, wears away, weathers, or show signs of irregularities.
• Drag - 1. A force that acts against air. The drag a vehicle produces can be determined by measurement of its drag coefficient. The coefficient pertains to aerodynamics, or the way a vehicle passes through air. The greater the drag on a vehicle, the more force it will have to contend with during acceleration and high speeds. 2. Drag can also refer to drag racing, which is a form of racing where a car must reach maximum speed in a straight line of a specific distance, such as a 1⁄4 mile.
• Drift (aka sliding, fish-tailing) - A maneuver in which the rear slip angle becomes greater than the front slip angle during acceleration or emergency braking. This can also can be caused by extreme weather or bad road conditions.
• Drivetrain - An engine and transmission (can also include differential and axles).
• Dyno (aka dynamometer) - A machine that measures wheel horsepower and torque by calculating forces from the ECU and/or driven wheels. Custom tuning also often involves a dyno in order to measure the results and efficiency of a tune.
• Four-Stroke Engine Cycle (aka four cycle) - A style of Engine cycle in which the Piston produces four reciprocating strokes while rotating the Crank. A full four-stroke cycle includes the intake (piston goes down in order to vacuum air-fuel mixture into the cylinder), compression (piston goes up to compress the air-fuel mixture as the intake valves close), power (the Spark Plug ignites the compressed air-fuel mixture which forces the piston downward), and exhaust stroke (the piston goes up to expel and push out the ignited Exhaust Gases through the exhaust Valves, and then the entire process repeats).
• Freight - A form of shipping that involves heavy items and freight carrier trucks. Services like business, residential, and liftgate delivery are popular options for freight delivery.
• Horsepower - A function of torque multiplied by RPM and then divided by 5252 (if measuring imperial horsepower) or 5180 (if measuring metric horsepower). The equation is noted in this formula: H = (T x RPM) / 5252 or 5180. One horsepower also equals to 33,000 lb-ft/min.
• JDM (aka Japanese Domestic Market) - A term that encompasses the culture of Japanese motorsports, vehicle design, engineering, industry, style, and more.
• Kilometers (aka KM) - A unit of measurement of distance. One kilometer is equal to 1000 meters or about 0.62 miles. 100,000 KM is equal to about 62,137 miles.
• Leverage - Using situations or events to maximum advantage, especially in business dealings and negotiations.
• LHD (aka left hand drive) - A style of vehicle that has steering, pedal, braking, and instrument panel components situated on the left hand side. These vehicles are usually built for markets like the US and other countries that drive on the right side of the road.
• Liftgate (aka dropgate) - A mechanical device that freight carriers use to lower an item, such as a pallet, from their elevated trailers down to floor level. A pallet jack is typically used to maneuver the item once lowered.
• Manufacturer - A producer of branded goods. Manufacturers of vehicles, such as Toyota, Subaru, etc., generally produce and assemble items under their brand name, including engines, frames, and other mechanical parts.
• Mechanic’s Special - A term used to describe an Engine or item that requires rebuilding or should only be used for parts. A “mechanic’s special” item is usually sold as-is without any warranty.
• Miles (aka mi.) - A unit of measurement of distance. One mile is equal to 5,280 feet or about 1.609 kilometers. 100,000 mi. is equal to about 160,934 KM.
• Modification - Altering the appearance or performance of a specific part of a vehicle or Engine.
• Monozukuri - The Japanese science and craft of making things well.
• Naturally Aspirated (aka N/A, normally aspirated) - When an Engine is introduced air solely by atmospheric pressure with no Forced Induction System.
• Payment Method - The form of payment used to complete the purchase of an item including credit/debit card, cash, check, or online payment services.
• Play - Movement from side to side and front to back. As an example, Play can be present in Suspension parts (due to wearing Bushings) and Turbocharger compressor wheel shafts.
• Rebuild - A loose term for the removal, disassembly, and reconstruction of a device such as an Engine, Transmission, Alternator, Turbo, or other parts. A rebuild can also refer to both a partial and complete rebuild.
• RHD (aka right hand drive) - A style of vehicle that has steering, pedal, braking, and instrument panel components situated on the right hand side. These vehicles are usually built for markets like Japan and other countries that drive on the left side of the road.
• RPM (aka revolutions per minute) - The amount of rotations a Crankshaft makes within one minute. RPMs are a measurement of engine speed (how fast it is running).
• Shaken - Japan’s national vehicle inspection program.
• Stance - A term used to describe the appearance of a certain kind of tuner vehicle. Key features of stance include extreme Camber, low or adjustable ride height, air bags suspension, stretched Tires, wide Rims, and more.
• Title (aka car title, certificate of title, pink slip) - A legal certificate showing ownership of a vehicle. VIN identification numbers as well as year, make, and model details are present on the title.
• Top Dead Center (aka TDC) - The position of the Crank when a specific Piston is at its farthest point from the crankshaft in terms of distance.
• Torque - 1. The rotational force produced by the Engine. Torque is typically measured in pound-feet (lb./ft) and newton-meters (NM). 2. The amount of force required for certain fasteners such as head bolts, wheel lug nuts, etc. to be firmly and safely tightened and locked down (known as static torque). Static torque is also measured in pound-feet and newton-meters.
• Tuning - A term that refers to the modification, adjustment, or reconfiguration of a particular system of a vehicle. Tuning can include changes or
upgrades to the engine, exterior, air-fuel ratios, suspension, and more.
• Tune-up - Routine maintenance performed on a vehicle. Certain parts of a tune-up may need to be replaced sooner than others (such as Spark Plugs or Distributor Caps), while major services like the replacement of the Water Pump and Timing Belt may need replacement much less frequently.
• Two-stroke cycle engine (aka two cycle) - An engine type in which the Piston produces two strokes during a single Crankshaft rotation to complete its cycle and is common in certain motorcycles and older vehicles.
