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    1952 Lincoln Capri 5.2L 2BL 8cyl

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    405 N COLLEGE ST
    (479) 443-4043

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    GLOSSARY TERMS

    T

    T
    Model T Ford.
    Any hot rod based on Model T stock, repro chassis, and/or body.
    T-Bone
    For one vehicle to strike another broad side.
    T-Bucket
    A Model T Ford roadster.
    T-Head Engine
    A flathead engine having intake valves on one side and exhaust valves on the other side of the cylinders.
    T-Top
    A partially removable car roof with panels above both front doors that may be lifted out.
    T-Tub
    A term used for T-bucket.
    TAC
    An abbreviation for thermostatically controlled air cleaner.
    Tach
    An abbreviation for tachometer.
    Tach-dwell Meter
    An instrument used to measure engine speed and distributor dwell.
    Tachometer
    An instrument used to measure engine speed.
    Tack Cloth
    A varnish-coated cheese cloth having a tacky surface used to clean metal prior to painting.
    Tack Rag
    A term used for tack cloth.
    Tack Weld
    A weld made to hold the parts of a weldment in proper alignment until the final welds are made.
    Tag Axle
    The rearmost axle of a tandem-axle tractor used to increase the load-carrying capacity of the vehicle.
    Tail Lights
    Lights used on the rear of a vehicle.
    Tailgate
    The rear opening of a station wagon or a van.
    To follow another vehicle closely.
    Tailpipe
    The pipe from the muffler or catalytic converter to the rear of the vehicle.
    The outlet pipe from the evaporator to the compressor.
    Tall Block
    An engine assembly consisting of a short block and cylinder heads.
    Tall Gear
    A final drive assembly with high gearing.
    Tall-Deck Engine
    An engine-block design height that permits a longer crank throw, or stroke.
    Tandem
    One directly in front of the other and working together, such as the rear wheels of a tractor.
    Tandem Drive
    A two-axle drive combination.
    Tandem Master Cylinder
    A master cylinder that consists of a single bore with two pistons and separate fluid compression chambers used with split braking systems to ensure that there will be some braking power in one braking circuit, even if there is a severe fluid loss in the other.
    Tandem-Axle Drive
    A type of drive that combines two single axles through the use of an interaxle differential or power divider and a short shaft that connects the two.
    Tandem-Axle Suspension
    A suspension consisting of two axles with a means for equalizing weight between them.
    Tang
    A projecting piece of metal placed on the end of the torque converter on automatic transmissions, used to rotate the oil pump.
    Tank
    A container for vapor or fluid such as an expansion tank or a header tank.
    Tank Unit
    That part of a fuel-indicating system that is mounted in the fuel tank.
    Tank-Vapor Space
    The area above the fuel level provided as a breathing space for the liquid-vapor separator and to compensate for expansion of fuel by heat.
    Taper
    A cylindrical part, solid or hollow, that is larger at one end than at the other.
    Taper-Bored Piston Pins
    Piston pins having tapered bores to reduce weight and add strength.
    Tapped Resistor
    A fixed resistor having two or more taps to provide different resistance values, as for fan speed control.
    Tappet
    A mechanical, solid-valve lifter located between the camshaft and valve stem, usually on L-head engines.
    Tar Paper
    A vinyl roof covering.
    TARA
    An abbreviation for Truck-Frame and Axle Repair Association.
    Targa
    A two-passenger convertible with a roll bar behind the seat, introduced by Porsche in 1965.
    Tarp
    An abbreviation for tarpaulin.
    Tarpaulin
    A cover used to protect the passenger compartment of an open car when the seat is not occupied.
    A cover used to protect the cargo bed of a pickup truck.
    Taxable Horsepower
    The power of a vehicle engine calculated by a formula providing a uniform comparison that is used for licensing vehicles in some areas.
    Taxi
    Short for taxicab.
    Taxicab
    A vehicle for hire.
    A racing vehicle that looks like an ordinary passenger car.
    TBI
    An abbreviation for throttle-body injection.
    TCS
    An abbreviation for transmission controlled spark.
    TDC
    An abbreviation for top dead center.
    TE
    An abbreviation for top eliminator.
    Tech
    Short for technical inspection or technician.
    Technical Inspection
    The examination of vehicles before an event to ensure that they conform to the rules.
    Technical Service Bulletin (TSB)
    The periodic information provided by the vehicle manufacturers regarding any problems encountered on current-year model vehicles.
    Technician
    One involved in the design, operation, or repair of a vehicle.
    Tee pee Exhaust
    An exhaust system for the Volkswagen Beetle engine.
    Teething Troubles
    Having difficulties with a new part or with a new vehicle.
    Teflon Pin Button
    A Teflon piston-pin retainer that fits between the pin and cylinder wall.
    TEL
    An abbreviation for tetraethyl lead.
    Telescoping Shock Absorber
    A shock having certain working parts that move in and out during compression and rebound.
    Television-radio-Suppression Cables
    A term used for spark plug wires or high tension cables.
    Temp Stick
    Short for temperature stick.
    Temper
    The measure of a metal's hardness.
    To heat treat metal to reduce brittleness.
    Temperature
    A measure of heat intensity.
    Temperature Gauge
    A device that provides a visual indication of temperature.
    Temperature Glide
    The range of an evaporating or condensing temperature for a given pressure.
    Temperature Indicator
    A gauge or lamp to warn of an overcooling or overheating condition.
    Temperature Rating
    The temperature-resistance ratings that indicate a tire's ability to withstand heat.
    Temperature Sending Unit
    A device in contact with the engine coolant that changes resistance, depending on its temperature, and sends a voltage signal to the gauge or lamp.
    Temperature Sensing Bulb
    A term used for remote bulb.
    Temperature Stick
    A stick-like crayon designed to melt at a specific temperature when rubbed on a heated surface.
    Temperature-Regulated Valve
    A term used for hot-gas bypass valve.
    Temporary Strainer
    A device installed during the run-in period of a new or rebuilt system, intended to remove coarse debris particles present in the system. After a suitable period it is removed, cleaned, and stored for future use.
    Temporary-use-only Spare Tire
    A term used for compact spare tire.
    Ten Tenths
    Great performance by an individual.
    Tensile Failure
    Failure in a synchronous belt drive caused by mishandling, misalignment, overloading, shock loads, or by large debris entering into the drive.
    Tensile Member
    The muscle of the belt whose purpose is to withstand the tension that is imposed to transmit the desired power.
    Tensile Strength
    The maximum tension a metal can withstand without breaking.
    Tension-loaded ball Joint
    A suspension component mounted in the lower control arm with the ball-joint stud facing upward into the knuckle so the vehicle weight tends to pull the ball out of the joint.
    Tenths
    A measure of personal performance as rated on a scale of one-tenth to ten-tenths.
    Terminal
    A battery post or connector.
    An electrical connector.
    Terminal Speed
    The maximum speed, in drag racing, that a vehicle achieves when passing through the traps at the end of the strip.
    Ternary
    Having three parts, elements, or divisions.
    Test Lamp
    A term used for test light.
    Test Light
    A small, non-powered or self-powered light used to determine electrical continuity in a circuit.
    Test Wheel
    A controlled procedure by the National Highway Traffic Safety Administration (NHTSA) to perform laboratory tests for temperature-resistance testing of automotive tires as determined by how long the tire lasts on the test wheel. The ratings are A, B, or C, with an A rating having the best temperature resistance.
    Tetraethyl Lead (TEL)
    A chemical, Pb(C2H5), once added to gasoline to increase its octane and aid in lubrication of the valves. Lead damages catalytic converters and oxygen sensors and therefore cannot be used in vehicles designed to operate on unleaded fuel. Leaded gasoline is no longer sold in the United States.
    Tetrafluoroethane
    The chemical name for the ozone-friendly refrigerant commonly known as HFC-134a or, more simply, R-134a. Its chemical symbol is CH2FCF3.
    Thermactor
    An air pump or air-aspirator, air-injection system by Ford.
    Thermactor Pump
    A device that injects ambient air into the exhaust system.
    Thermal
    Pertaining to heat.
    Thermal Cutting
    A cutting process that removes metal by localized melting, burning, or vaporizing of the work piece.
    Thermal Delay Fuse
    A device once used in conjunction with the compressor protection switch that heats and blows a fuse to stop a compressor action during abnormal operation.
    Thermal Efficiency
    The difference between potential and actual energy developed in a fuel measured in Btu's per pound or gallon (kilogram or liter).
    Thermal Fuse
    A temperature-sensitive fuse link designed so that it melts at a certain temperature and opens a circuit.
    Thermal Limiter
    An electrical or mechanical device, similar to a fuse, that opens at 300°F (149°C) to control the intensity or quantity of heat.
    Thermal Reactor
    An obsolete early attempt of an emissions-control device comprising a large, heavy, exhaust manifold in which hydrocarbons and carbon monoxide that escape from the cylinders are oxidized.
    Thermal Stability
    The ability of a device to reach and maintain a specific temperature for a long period of time.
    Thermistor
    A resistor that changes resistance values depending on its temperature.
    Thermit Reaction
    The chemical reaction between metal oxide and aluminum that produces superheated molten metal and a slag containing aluminum oxide.
    Thermostat
    A driver-operated device used to cycle the clutch to control the rate of refrigerant flow as a means of temperature control.
    A temperature-sensitive component located in a housing at the coolant outlet of the engine that restricts coolant flow to the radiator to maintain the desired engine-operating temperature. Often referred to as Ranco control.
    Thermostatic Air Cleaner
    An engine air-cleaner assembly that controls the temperature of the intake air by blending relatively cool underhood or outside air with relatively hot air picked up from a shroud over the exhaust manifold.
    Thermostatic Clutch Control
    A method of temperature control using a thermostat to cycle a clutch on and off.
    Thermostatic De-icing Switch
    A thermostat that prevents the evaporator from icing up due to low temperature conditions.
    Thermostatic Expansion Valve
    The component of a refrigeration system that regulates the rate of flow of refrigerant into the evaporator as governed by the action of the remote bulb-sensing tailpipe temperatures.
    Thermostatic Gauge
    A type of gauge used to indicate fuel level, oil pressure, and engine-coolant temperature.
    Thermostatic Pressure Valve
    A valve that opens and closes in relation to temperature changes.
    Thermostatic Switch
    A term used for thermostat.
    Thermostatic Vacuum Switch (TVS)
    A valve that controls the passage of vacuum according to temperature, blocking vacuum until a certain coolant temperature is reached, at which point it opens.
    Thermostatic Vacuum Valve (TVV)
    A valve that is operational with a vacuum signal that is proportional to an applied temperature.
    Thermostatically Controlled Air Cleaner (TCAC)
    A device used to regulate the temperature of the air entering the engine air cleaner as an aid in reducing emissions.
    Thermosyphon
    The flow of coolant in a heat exchanger, such as a radiator, that is possible by the difference in densities of heated and cooled fluid.
    Thin Wall Guide
    An insert that may be used to repair a damaged valve guide.
    Thinner
    A solvent used to reduce the viscosity of a liquid.
    Third Gauge
    A low-side gauge used to check pressure drop across a suction-pressure regulator at the compressor inlet on some car lines.
    Third Law of Motion
    For every action there is an equal and opposite reaction.
    Third Member
    A differential.
    Thou
    A term used for thousandths, as in a measurement or thousands, as in revolutions per minute.
    Thousand
    A number equal to ten times one hundred.
    Thousandths
    One part of a thousand.
    Thread Class
    A standard designation to indicate the closeness of fit between two threaded parts, such as a bolt and nut.
    Thread Series
    A standard designation of the number of threads and their pitch per unit, inch or millimeter.
    Threaded Fastener
    Any of several types of components that hold parts together in assembly by interference of screw threads with mating threads in another component, such as capscrews, self-threading screws, stud-and-nut, and bolt-and-nut assemblies.
    Threaded Insert
    A threaded coil that is used to repair a damaged internal thread.
    Three on the Tree
    A three-speed manual transmission having a column-mounted shifter.
    Three Phase
    A type of electrical power such as that produced by an alternator.
    Three Piece Valve
    An intake or exhaust valve made of three different types of material in the head, stem, and tip.
    Three-Mode Cycle
    A quick test procedure to study the causes of high emissions performed on a dynamometer under load or in a service bay without a load.
    Three-Speed Differential
    A type of two-speed axle arrangement with the capability of operating both axles at a different speed at the same time. The third speed is actually an intermediate speed between the high and low range.
    Three-Speed Transmission
    A transmission providing three forward-gear ratios, one reverse gear ratio and neutral.
    Three-Way Catalyst (TWC)
    A catalytic converter that oxidizes hydrocarbons and carbon monoxide and reduces oxides of nitrogen (NOX) emissions. It has a chamber upstream handling reduction, and one downstream handling oxidation.
    Three-Window Coupe
    A coupe without rear-quarter windows.
    Threshold Limit Value
    The percentage, in parts per million (ppm), of refrigeration in atmospheric air above which a human can become drowsy or have loss of concentration.
    Throat
    The lower part of a connecting rod.
    A carburetor barrel.
    Throttle
    A hand control to adjust engine speed.
    An accelerator pedal.
    Throttle Body
    The housing of a throttle-body injection system that contains the valves.
    Throttle Cut-out Relay
    A term used for wide-open-throttle cut-out relay.
    Throttle Plate
    A term used for throttle valve.
    Throttle Position Sensor
    A variable three-wire resistor-type electrical sensor which sends a signal to the electronic control unit relative to the throttle position.
    Throttle return Check
    A dashpot.
    Throttle Solenoid Positioner
    An electric device that holds the throttle plate in the hot-idle position and closes it when the ignition switch is turned off.
    Throttle Valve
    A flap valve that controls the amount of air admitted into the induction system.
    Throttle-Body Injection
    A term used for throttle-body injection system.
    Throttle-Body Injection System (TBI)
    A fuel-injection system that resembles a carburetor and has fuel injectors located in a common throttle body. It provides many of the advantages of fuel injection, such as easier starting and lower emissions, without the cost and complexity of a multiport-injection system.
    Throttling Valve
    A term used for throttle valve, suction throttling valve, or evaporator pressure regulator.
    Throw
    A connecting rod journal on a crankshaft.
    The number of output circuits on a switch.
    Throw a Rod
    A loose connecting-rod bearing.
    A broken connecting rod that has been forced through the block or oil pan.
    Throwout Bearing
    The clutch-release bearing.
    Thrust Bearing
    A bearing or a part of the main bearing that limits end-to-end movement of the crankshaft.
    Thrust Load
    Load placed on a part that is parallel with the center of the axis.
    Thrust Plate
    A retainer that positions the camshaft in an OHV engine and limits its end-to-end movement.
    Thrust Surface
    The area of a crank or block that absorbs end-to-end thrust pressure.
    Thrust Washer
    A washer that is capable of supporting a thrust load.
    Thumbnail Grooves
    Small grooves in a thrust bearing that provide a path for lubrication to the thrust surfaces.
    Tie Rod
    The linkage between the idler arm or pitman arm and the steering arm.
    Tie-Rod Coupling
    A threaded sleeve between the tie rod and the tie-rod end providing lengthwise adjustment to set front-wheel toe in.
    Tie-Rod End
    A pivoting ball-and-socket joint located near the outer end of the tie rod used to connect the tie rods to the center link and to the steering arms.
    TIG
    An abbreviation for tungsten inert gas.
    TIG Welding
    A welding process using tungsten (W) and an inert gas such as Argon (Ar).
    Tijuana Chrome
    Silver, chrome, or aluminum spray paint.
    Tilt Steering Wheel
    A type of steering wheel that can be tilted to various angles to provide for driver comfort and convenience.
    Time Guide
    A reference, providing average time required to perform specific repairs or service to a motor vehicle, that may be used as a labor charge based on an hourly rate.
    Time Trials
    Timed runs for individual race vehicles, usually to determine starting positions for a race.
    Time, Speed, and Distance (TSD)
    A type of rally where the object is to cover the greatest distance in the shortest period of time without exceeding the speed limit.
    Timing
    The combustion spark delivery in relation to the piston position.
    The procedure of marking the appropriate teeth of a gear set prior to installation and placement in proper mesh.
    Timing Belt
    The belt through which the crankshaft drives the camshaft or camshafts in an overhead valve or overhead cam engine.
    Timing Chain
    The chain through which the crankshaft drives the camshaft or camshafts in an overhead valve or overhead cam engine.
    Timing Diagram
    A graphical method used to identify the time in which all of the events of the four-stroke engine operate.
    Timing Gear
    The gear or gears through which the crankshaft drives the camshaft or camshafts in an overhead valve or overhead cam engine.
    Timing Light
    A stroboscopic tool used to check the precise timing of a conventional ignition, adjusted by loosening the holddown bolt and turning the distributor.
    Timing Valve
    A device in the fuel-injector pump which times the delivery of fuel to the injectors.
    Tin
    An element (Sn).
    A term often used for metal.
    Tin Indian
    A Pontiac.
    Tin Knocker
    One who repairs auto bodies.
    Tin Top
    A vehicle with a fully enclosed body.
    Tin Work
    Auto bodywork.
    Tin Worker
    One that works on vehicle bodies.
    Tinny
    A station wagon having an all metal body.
    Tip Insert
    A term used for leaf-tip insert.
    Tip the Can
    To increase the ratio of nitro in a racing-fuel mixture.
    Tire
    An air-filled or solid covering for a wheel, normally of rubber.
    A device made of rubber, fabric and other materials that, when filled with fluid or gas under pressure and mounted on a wheel, cushions and sustains the imposed load. Tires contribute to the ride and steering quality of a vehicle and play a significant role in vehicle safety. Tires must be designed to carry the weight of the vehicle, transfer braking and driving torque to the road, and withstand side thrust over varying speeds and conditions.
    Tire Aspect Ratio
    A term used for aspect ratio. Also known as series number.
    Tire Balancing
    The procedure of using special equipment for identifying the lighter portions of a tire and adding weights until opposite tire sections weigh the same.
    Tire Bead
    A term used for bead.
    Tire Belt
    A term used for belt.
    Tire Black
    A black liquid dressing used to refresh the appearance of tires.
    Tire Carcass
    The plies that make up the underbody of the tire.
    Tire Casing
    Layers of cord called plies on which the rubber tread is applied.
    Tire Chain
    Specialty chains which may be placed over the tires to improve traction when driving on ice or snow; typically used in emergency situations such as driving on snow-covered or ice-covered mountain roads.
    Tire Coding
    Information required by federal legislation to be placed on all tires, such as manufacturer and tire name, size designation, maximum load-carrying characteristics, limit, and range, a ten-digit Department of Transportation serial number indicating where and when it was made, and the letter A, B, or C, indicating conformity to a uniform tire quality grading system.
    Tire Conicity
    A condition where the plies and/or belts are not level across the tire tread and are somewhat cone shaped. This causes a pull to one side as the car is driven straight ahead if the tires are on the front of the vehicle.
    Tire Construction
    A typical, modern, tire-construction design has two wire beads, bead filler, liner, steel reinforcement in the sidewall, sidewall with hard side compound, rayon carcass plies, steel belts, jointless belt cover, hard under-tread compound, and hard high-grip tread compound.
    Tire Contact Area
    The footprint, patch, or patch area of the tire that is in contact with the road surface when the tire is supporting the vehicle weight.
    Tire Deflection
    The difference between the free diameter and the rolling diameter of the tire.
    Tire Design
    The three basic tire construction designs are based on the arrangement of the body plies bias, belted radial, and belted bias. A bias-ply tire is constructed with the plies arranged on a bias crossing each other. A belted radial-ply tire is constructed with plies that run at right angles to the circumference of the tire. A belted bias-ply tire is constructed with reinforcing belts beneath the tread section.
    Tire Free Diameter
    The free diameter of a tire is the distance of a horizontal line through the center of the spindle and wheel to the outer edges of the tread.
    Tire Functions
    To cushion the vehicle ride to provide a comfortable ride for the occupant; reduces jolts to the vehicle caused by road irregularities.
    To support the vehicle weight.
    To develop traction to drive and steer the vehicle under a wide variety of road conditions.
    To contribute to the directional stability of the vehicle, and absorb all the stresses of accelerating, braking, and centrifugal force in turns.
    Tire Industry Safety Council (TISC)
    A public education organization.
    Tire Inflation
    Air pressure inside the tire, measured in pounds per square inch (psi) or kilopascals (kPa), checked when tire is cool or has been driven less than one mile.
    Tire Life Expectancy
    The expected service life of a tire based on its tread wear rating and uniform tire quality grading.
    Tire Manufacturer's Code
    A term for manufacturer's code.
    Tire Mixing
    Having more than one size tire on a vehicle. Tires should be replaced only with those recommended by the vehicle manufacturer. Using incorrect or improper tires can cause the vehicle to handle improperly and may result in an accident.
    Tire Motion Forces
    Forces that affect a tire in motion, including centrifugal, acceleration, and deceleration forces.
    Tire out of Roundness
    The lateral runout or radial runout of a tire.
    Tire Performance Criteria
    Information molded on the tire sidewall indicating that the tire meets the manufacturer's performance standards for traction, endurance, dimensions, noise, handling, and rolling resistance.
    Tire Placard
    A label that is permanently attached to the rear face of the driver's door of most vehicles providing information such as maximum vehicle load, tire size, including spare, and cold inflation pressure, including spare.
    Tire Profile
    The profile of a tire is based on the width and height of a cross section of the tire determined by an aspect ratio equal to the section height divided by the section width.
    Tire Pucker
    A tire tread that has pulled up on the edges due to mounting on a too-narrow wheel.
    Tire Purposes
    A term used for tire functions.
    Tire Rim
    A term used for wheel rim.
    Tire Rolling Diameter
    The distance of a perpendicular straight line through the center of the spindle to the outer edges of the tread when the tire is supporting the vehicle weight.
    Tire Rotation
    Swapping tires around to various positions, as prescribed by the tire manufacturer, on the vehicle to equalize tire wear.
    Tire Runout
    The lateral runout and radial runout of a tire.
    Tire Scrub
    The sliding of a tire at an angle to the direction that it is pointed.
    Tire Shimmy
    An out-of-balance condition called wheel shimmy.
    Tire Sidewall
    That area of the tire between the bead and the tread pattern made from an abrasive-resistant blend of rubber, which absorbs shocks and impacts from road irregularities and prevents damage to the plies.
    Tire Stagger
    Providing different size tires on each side of the axle of an oval- track race car to compensate for all left turns.
    Tire Tramp
    A term used for wheel tramp.
    Tire Tread
    A term used for tread.
    Tire Trueing
    Procedure of rounding a tire by removing rubber so the tread face forms a true circle. This is done by removing high-tread areas while revolving the tire.
    Tire Valve Stem
    A term used for valve stem.
    Tire Waddle
    The side-to-side movement at the front and/or rear of the vehicle caused by the steel belt not being straight within the tire. This is most noticeable at low speeds of 5 to 30 mph (8 to 48.3 km/hr).
    Tire Wear Pattern
    A term used for wear pattern.
    Tire's area of Contact
    A term used for footprint or tire contact area.
    Tire-Speed Rating
    A tire rating that specifies the speed at which the tire can be safely used and does not suggest that a vehicle can be driven safely at the designated speed, because of various road and weather conditions that may be encountered. Also the condition of the vehicle may affect high-speed operation.
    TISC
    An abbreviation for Tire Industry Safety Council.
    TMC
    An abbreviation for Tune-Up Manufacturers Council.
    Toe
    The end of the brake shoe against the anchor.
    Toe In
    The amount by which the front of a front wheel points inward.
    Toe Out
    The amount by which the front of a front wheel points outward.
    Toe Out on Turns
    The difference between the angles each of the front wheels makes during a turn.
    Tolerance
    The allowable variation from a standard specification.
    Toluene
    A colorless, flammable liquid hydrocarbon, C6H5CH3, used as a cleaning solvent.
    Ton
    A speed of 100 miles-per-hour.
    A unit of weight regarded as 2,000 pounds (907.2 kilograms).
    Ton of refrigeration
    The effect of melting one ton of ice in 24 hours equal to 12,000 Btu per hour.
    Tongue Weight
    The load applied to the hitch by the trailer tongue, equal to about 10–15 percent of the trailer gross weight.
    Tonneau Cover
    An up term used for tarpaulin.
    Tooling
    A set of required standard or special tools needed to produce a particular part, including jigs, fixtures, gauges, and cutting tools, but excluding machine tools.
    Tooth
    A projection on a gear rim or synchronous belt that meshes or engages with another component.
    Tooth cracks
    In a synchronous belt drive, tooth cracks and eventual tooth separation can be caused by under tensioning, over tensioning, or using a backside idler with too small a diameter or as a result of an under-designed belt drive.
    Tooth form
    The shape of the working surface of a sprocket tooth from the bottom of the seating curve up through the working faces to the tip of the tooth.
    Tooth separation
    A tooth crack.
    Top Dead Center (TDC)
    The piston position at the top of its stroke.
    Top Eliminator (TE)
    The overall winner in a series of drag races.
    Top End
    High engine rpm; a point that horsepower is the greatest.
    The far end of a quarter-mile drag strip.
    Top Fuel
    The hottest category in drag racing having cars capable of a quarter mile in less than five seconds, and a top speed of over 300 mph (482.7 km/h).
    Top Inch
    The first downward inch of a piston stroke where most wear occurs.
    Top Loader
    A Ford four-speed transmission of the mid 1960s to early 1970s.
    Top Ring
    The top ring of a piston.
    Top Time (TT)
    The speed at which a vehicle passes through the traps at the end of a quarter mile.
    Top U-bolt Plate
    A plate located on the top of the spring and held in place when the U-bolts are tightened, clamping the spring and axle together.
    Top-End Power
    The engine output at high speed.
    Top-Mount Battery
    A battery having terminals located at the top of the case.
    Topcoat
    Usually the final paint film applied to a surface.
    Torching
    The cutting or burning of a valve face caused by excessive detonation.
    To flame-cut metal.
    Torque
    The measure of a force-producing tension and rotation around an axis.
    Torque and Twist
    The forces developed in the trailer and/or tractor frame that are transmitted through the fifth wheel when a rigid trailer, such as a tanker, is required to negotiate bumps, such as street curbs.
    Torque Converter
    Unit that transfers power from the engine to the transmission input shaft by directing and redirecting fluid flow.
    Torque Multiplication
    Torque increase as a result of converter action that allows the turbine to revolve slower than the impeller during acceleration and heavy-load conditions at a ratio as much as 2:1.
    Torque Plate
    A thick, metal plate bolted to the deck of a block during cylinder boring and honing to reproduce the stress caused when the heads are installed and the bolts are properly torqued.
    Torque Rod Shims
    Thin metal shims used to rotate the axis pinion to change the operating angle of the U-joint.
    Torque Sequence
    The order in which a series of bolts or nuts should be tightened.
    Torque Spec
    The force required to tighten a nut or bolt.
    Torque Steer
    An outside influence, such as uneven front tire-tread wear, causing the steering wheel to turn right or left during hard acceleration, relating to the dual torque and steering requirements that are applied to the drive axle of front-wheel-drive vehicles.
    Torque Test
    A starting motor test to determine torque produced and current required while the specified voltage is applied.
    Torque Tube
    A drive-shaft system that is enclosed in a tube extending from the transmission tailshaft to the rear-axle housing.
    Torque Wrench
    A wrench that indicates the amount of torque being exerted when used, to enable threaded parts to be tightened a specified amount.
    Torque-Limiting Clutch Brake
    A system designed to slip when loads of 20 to 25 foot pounds (27??33.8 N*m) are reached in order to protect the brake system from overload and high heat damage.
    Torque-to-Yield Bolt
    A bolt that has been tightened to a specified yield or stretch point.
    Torqueflite
    A three-speed, plus reverse, automatic transmission used by Chrysler.
    Torsion Bar
    A long, spring-steel bar replacing the coil springs, connected from the chassis to the lower control arm, to provide the necessary springing effect on the front suspensions by twisting rather than compressing or bending.
    Torsion-Bar Spring
    A term used for torsion bar.
    Torsion-Bar Steering gear
    A rotary valve power-steering gear.
    Torsion-Bar Suspension
    A suspension featuring a torsion bar rather than a coil or leaf spring.
    Torsional Balancer
    A term used for vibration damper.
    Torsional Rigidity
    The resistance of a structure to twisting and flexing.
    Torsional Rings
    Rings that have a slight twist when placed within the cylinder wall, made by adding a chamfer or counterbore on the ring.
    Torsional Stabilizer Bar
    A stabilizer bar made of spring steel reduces the body roll, thereby reducing the effect of centrifugal force when a vehicle rounds a corner.
    Torsional Vibration
    A rotary vibration that causes a twist-untwist action on a rotating shaft.
    Torx Fastener
    A six-point fastener that is easy to grip and drive without slippage. Sometimes called a star fastener, this relatively new fastener is used on most late model cars in luggage racks, headlights, tail-light assemblies, mirror mountings, and exterior trim.
    Total Heat Load
    The amount of heat to be removed or added, based on all conditions.
    Total Pedal Travel
    The complete distance a clutch pedal must move to disengage the flywheel.
    Total Volume
    Volume of space in the cylinder and combustion chamber above the piston at bottom dead center (BDC).
    Totalled
    The condition of a vehicle that has been damaged beyond repair.
    Tow Truck
    A truck set up to pull a trailer or other vehicle.
    Tow Vehicle
    A vehicle set up to pull a trailer or other vehicle.
    Town Car
    A four-door, chauffeur-driven sedan with an open cockpit and an enclosed passenger compartment.
    Toxicity
    A measure of how poisonous a substance is.
    TPC Designation
    A term used for tire performance criteria.
    TPI
    An abbreviation for tuned port injection.
    Trace
    A colored dye introduced into a system to detect leaks.
    To follow logically from beginning to end.
    A bar hinged to two parts to transfer motion between them.
    Track
    A term used for tread.
    The roadway or pathway a vehicle travels during a competitive event.
    To follow.
    A belt or tread that guides lines of motion.
    Track Bar
    A steel bar attached to the axle housing on one side and the frame on the other side of the vehicle to maintain sideways alignment between the axle housing and frame on some coil-spring equipped models.
    Tracking
    Rear wheels following directly behind the front wheels.
    Traction
    A body's friction on a surface such as a vehicle tire on a roadway.
    Traction Bar
    A device used on a rear-wheel-drive vehicle to prevent axle twist and spring wind up during hard acceleration.
    Traction Rating
    A tire rating that indicates the traction capabilities of the tire to the consumer.
    Traction-Lok
    A limited-slip differential by Ford.
    Tractive Effort
    The pushing force exerted by the vehicle's driving wheels against the road's surface.
    Tractor
    A term used for truck tractor.
    A motor vehicle having a fifth wheel used for pulling a semitrailer.
    A truck or short wheel-base vehicle used for pulling a trailer or semitrailer.
    A self-propelled vehicle having tracks or wheels.
    Tractor Breakaway Valve
    A device that automatically seals off the tractor air supply from the trailer air supply when the tractor system pressure drops to 30 or 40 psi (206.8 to 275.8 kPa).
    Tractor Protection Valve
    A term used for tractor breakaway valve.
    Tractor/Trailer Lift Suspension
    A single-axle air-ride suspension with lift capabilities commonly used with steerable axles for pusher and tag applications.
    Trail Braking
    A driving technique where the brakes are applied after entering a turn to help rotate the vehicle.
    Trailer
    A platform or container on wheels pulled by a truck or tractor.
    A non-powered vehicle used to haul cargo.
    To put on the trailer.
    Trailer Charge
    To fill the trailer air tanks with air by means of a dash control valve, tractor protection valve, and a trailer relay emergency valve.
    Trailer Hand-Control Valve
    A device located on the dash or steering column used to apply only the trailer brakes; primarily used in jack-knife situations.
    Trailer Slider
    A movable suspension frame that is capable of changing the trailer wheelbase by sliding and locking into different positions.
    Trailer Tongue
    An extension at the front of a trailer that attaches to a hitch ball on a tow vehicle.
    Trailing Arm
    A suspension arm that attaches to the chassis ahead of the wheel, generally for the rear wheels on a front-wheel drive vehicle.
    Trailing Shoe
    A shoe, toward the rear of a non-servo brake assembly, which pivots around a fulcrum in a direction opposite to normal drum rotation.
    Tramp
    A form of wheel hop where a pair of wheels on an axle hop in opposite phase due to axle windup.
    Tranny
    A term for transmission.
    Trans
    A term for transmission.
    Trans-Am
    An annual road-racing series, the oldest in the United States, for pony cars and small sedans.
    Transaxle
    A combination transmission-and-axle assembly, common in front-engine, front-drive vehicles.
    Transaxle Pinion Gear Shaft
    The shaft on which a pinion is found in a transaxle.
    Transducer
    A device that converts an input of one form into an output of another form, such as a motor that converts an electric signal to a rotary motion.
    Transfer Case
    A small transmission used on four-wheel-drive vehicles to transfer engine torque to the front and/or rear axles.
    Transfer Gears
    Gears used to transfer engine torque from one level to another in a transaxle.
    Transistor
    A semiconductor device for controlling the flow of current between two terminals, the emitter and the collector, by means of variations in the current flow between a third terminal, the base, and one of the other two.
    Transistorized Ignition
    An ignition system having conventional breaker points with transistor regulation of voltage.
    Transitional Spring coil
    Coils that become inactive when compressed to their maximum load-carrying capacity.
    Transmission
    A gearing device of a vehicle that provides variable ratios between the engine output and the differential input.
    Transmission Controlled Spark (TCS)
    An emissions-control system to prevent distributor vacuum advance at normal operating temperature until the transmission has shifted into high gear by using a transmission-mounted electric switch controlling a solenoid-actuated vacuum valve.
    Transmission Oil Cooler
    Heat exchanger located in the radiator outlet end section through which transmission fluid flows for cooling purposes on most automatic transmission cars.
    Transmission-regulated Spark System (TRS)
    A system that allows distributor vacuum advance only when the transmission is in high gear.
    Transplant
    An automobile factory operated by an automaker in a country other than its own, such as United States automaker's plants in Canada.
    An engine swap.
    Transverse Crack
    A crack with its major axis oriented approximately perpendicular to the weld axis.
    Transverse Vibration
    A vibration caused by an unbalanced drive line.
    Traps
    The measured section at the end of a drag strip.
    The fastest part of an oval track or road racing course.
    Trash Box
    An engine built from junk parts.
    A car built from junk parts.
    Travel
    A term used for rebound travel.
    To move or go from one place to another.
    Travel Trailer
    A trailer with living accommodations.
    Travel-Sensitive Strut
    A strut with the capability to adjust its firmness in relation to the amount of piston travel within.
    Traverse Engine
    An engine mounted sideways in a vehicle, such as in most front- drive vehicles.
    Traverse Leaf Spring
    A leaf spring mounted sideways, such as in the Model T, or Corvette.
    Tread
    That portion of a tire that comes into contact with the surface of the road and is designed to allow the air flow to cool the tire and to channel water during wet weather.
    Tread Compound
    A blend of synthetic rubber used in the tire tread material.
    Tread Distortion
    Tread shape change on certain tires as rotating contact is made with the road surface; less severe in belted tires.
    Tread Groove
    The recessed portion of the tire tread between the ribs.
    Tread Rib
    The raised portion of the tire tread between the grooves.
    Tread Rubber
    A blend of up to 30 different synthetic, and eight natural rubbers used in a tire tread.
    Tread-Wear Indicator
    Projections of rubber, 1/16 inch (1.59 mm) high at the bottom of the tread grooves, spaced around the tire to identify a tire worn to the recommended safe limit.
    Tread-Wear Rating
    A tire rating indicating the wear capabilities of the tread that allow consumers to compare tire life expectancy.
    Treadle
    A dual, heavy-truck brake valve that:
    Releases air from the service reservoir to the service lines and brake chambers.
    Opens ports to service lines to vent air in the primary and secondary systems.
    Tree
    A term used for Christmas tree.
    Tree Diagnostics Chart
    A flow chart that suggests logical procedures to follow when troubleshooting a problem.
    Tri-Chevy
    1955, 1956, and 1957 Chevrolets.
    Tri-Coat
    A painting system having three layers of topcoat paint.
    Tri-Oval Track
    A racing course with three high-banked turns such as at the Daytona International Speedway.
    Tri-Power
    A triple two-barrel carburetor setup.
    Triangulation
    The arrangement of frame members for greater durability and rigidity.
    Triaxle Suspension
    A suspension consisting of three axles with a means of equalizing weight between them.
    Trickle Charger
    A battery charger with a very low output.
    Triple Evacuation
    The process of evacuating a system that involves three pump downs and two system purges with an inert gas, such as dry nitrogen (N).
    Tripod
    The central part of certain CV joints having three arms or trunnions with needle bearings and rollers running in grooves or races in the assembly.
    Trophy
    An award for achievement, such as winning a race.
    Trophy Dash
    A short match, at the start of the event, among the fastest qualifying cars in an oval track race.
    Trophy Run
    A match for an individual class trophy in drag racing.
    Trouble Code
    A number generated by a computer to indicate a failure in a sensor, circuit, or the computer itself. The number may be communicated to the technician by the flashing of a dash light when the diagnostic mode is entered. Also known as failure code.
    Trouble Diagnosis
    The work required to find the cause of a problem.
    Troubleshooting
    The location of a problem or malfunction by a process of elimination.
    TRS
    An abbreviation for transmission-regulated spark system.
    Truck
    A large vehicle generally used for hauling cargo or for pulling a trailer.
    Truck Tractor
    A large truck with a fifth wheel used to pull a semitrailer.
    Truck-Frame and Axle Repair Association (TARA)
    A trade association of those engaged in repair of truck and heavy equipment frames.
    Trueing
    Straightening bent shafting or parts.
    Dressing a grinding wheel.
    Setting up a flywheel or pulley so that it runs evenly without sideways motion at its rim.
    Making an edge straight or bringing two parts square with each other.
    Trunk
    A storage compartment at the rear of most passenger cars.
    Trunk Unit
    An early automotive air-conditioning evaporator that mounted in the trunk compartment and was channeled through the package tray.
    Trunnion
    The ends of a universal joint cross where the bearings ride.
    Try-Y Headers
    An exhaust manifold setup that pairs cylinders according to their firing order to provide better exhaust scavenging.
    TSB
    An abbreviation for technical service bulletin.
    TSD
    An abbreviation for time, speed, and distance.
    TT
    An abbreviation for top time.
    Tub
    A term used for phaeton.
    A phaeton body.
    The external structure of an auto body.
    Tubbed
    A standard passenger-car body with cut-out rear wheel wells to accommodate oversize rear wheels.
    Tube-and-Fin Condenser
    A type of heat exchanger that consists of tubes to which fins are attached to facilitate the transfer of heat from the fluid passing through it to the air passing over it.
    Tube-and-Fin Evaporator
    A type of heat exchanger that consists of tubes to which fins are attached to facilitate the transfer of heat from the air passing over it to the fluid passing through it.
    Tube-and-Fin Radiator
    A type of heat exchanger that consists of tubes to which fins are attached to facilitate the transfer of heat from the fluid passing through it to the air passing over it.
    Tubeless Tire
    A tire having an integral inside rubber liner to retain air; mounted directly on the rim.
    Tubular Core
    A radiator or heater core made up of tubular cells.
    Tubular Pushrod
    A term used for hollow pushrod.
    Tucked and Rolled
    A type of upholstery pleating.
    Tudor
    An early Ford designation for a four-door sedan.
    Tuftride (210)
    The tradename of a liquid chemical used to surface-harden metal parts, such as crankshafts.
    Tules
    The boondocks or the back country.
    Tulip Valve
    An intake or exhaust valve with a tulip-shape on the backside of the valve head.
    Tune Up
    A routine maintenance procedure that includes replacing the rotor and spark plugs; in older cars, replacing the rotor, points, capacitor, spark plugs and adjustment of the timing.
    Tune-Up Manufacturers Council (TMC)
    A trade association for the manufacturers of ignition parts.
    Tune-up Specifications
    Specifications used during a tune-up procedure on a vehicle.
    Tuned Exhaust
    An exhaust system having equal length passages.
    Tuned Header
    A term used for tuned exhaust.
    Tuned Intake
    A term used for ram tuning.
    Tuned Port Injection (TPI)
    A multiport fuel-injection system used on 5.0 and 5.7 Liter General Motors V-8 engines featuring tuned intake runners from a common plenum.
    Tunes
    Slang for a stereo sound system.
    Tungsten Electrode
    A non-filler metal electrode used in arc welding, arc cutting, and plasma spraying, made principally of tungsten (W).
    Tungsten Inert Gas Welding
    A welding process using tungsten (W) with an inert gas, such as argon (Ar), as a shield.
    Tunnel Ram Manifold
    An intake manifold having a large plenum and long runners to the intake ports, improving output at high rpm.
    Turbine
    The driven member inside a torque converter consisting of many vanes that receive fluid flow from the impeller.
    Turbine Engine
    An engine in which gas pressure is created by combustion to spin a turbine.
    Turbo
    An abbreviation for turbocharger.
    Turbo Car
    A car with a turbine engine.
    Turbo Hydra-Matic
    An automatic transmission by General Motors.
    Turbo Hydro
    A term used for Turbo Hydra-Matic.
    Turbo Intercooler
    A term used for intercooler.
    Turbo Lag
    The short delay in engine response when a driver punches the throttle in a turbocharged vehicle.
    Turbocharger
    A turbine-type supercharger driven by exhaust gases.
    Turbosupercharger
    A term used for turbocharger.
    Turbulence
    A violent disturbance such as the rapid swirling motion of the air/fuel mixture entering a combustion chamber.
    Turkey Pan
    Flanges that are installed as deflectors in an engine to reduce oil splash in the lifter areas.
    Turn
    To change directions.
    A specific speed, as in to turn 90 mph.
    Turn Ratio
    The ratio between the number of turns between windings in a transformer, primary to secondary.
    Turn Signal
    Lights located at the four corners of a vehicle to signal a turn.
    Turning Circle
    A term used for turning diameter.
    Turning Diameter
    The diameter of a circle a vehicle would make if the steering were locked.
    Turning Torque
    Amount of torque required to keep a shaft or gear rotating.
    TVS
    An abbreviation for thermostatic vacuum switch.
    TVV
    An abbreviation for thermostatic vacuum valve.
    TWC
    An abbreviation for three-way catalyst.
    Twenty Five Ampere Rate
    A battery rating to indicate the time a fully charged battery at 80°F (26.7°C) can deliver 25 amperes before the cells drop to 1.75 volts.
    Twenty-Hour Rating
    The amount of current a battery can deliver for 20 hours at 80°F (26.7°C) without the cell voltage dropping below 1.75 volts.
    Twice Pipes
    A dual-exhaust system on a hot rod.
    Twin
    A two-cylinder engine.
    An identical pair.
    Twin Cam
    Dual overhead camshafts.
    Twin I-Beam
    A front suspension using two I-beams, each attached to the chassis at the end opposite the wheel, and a coil spring at the wheel end.
    Twin Torsion Bar
    A suspension system having two torsion bars, one placed above the other.
    Twin-Grip
    A limited-slip differential by AMC.
    Twin-Plug Head
    A cylinder head having provisions for two spark plugs per cylinder.
    Twin-Plug Ignition System
    An ignition system having two distributors, two coils, and two plugs per cylinder.
    Two Cycle
    A term used for two-stroke cycle.
    Two in the Glue
    A two-speed automatic transmission.
    Two Plus Two
    A term used for club coupe.
    A four or five passenger two-door auto body with limited rear-seat space.
    Two Speed Axle Assembly
    A heavy-duty, vehicle-axle arrangement having two different output ratios from the differential that are controlled from the cab or the truck.
    Two-Bolt Main
    An engine block in which the mains are held in place with two bolts each.
    Two-Piece Drive Shaft
    A type of drive shaft having two sections requiring a center support bearing mounted on the vehicle frame and universal joints at both ends and in the center.
    Two-Piece Piston
    A piston having a removable skirt.
    Two-Piece Valve
    A valve having a head and stem made of two different materials.
    Two-Plane Manifold
    An intake manifold with two plenums.
    Two-Stroke Cycle
    An engine in which the four events, intake, compression, combustion, and exhaust, take place in two strokes of the piston.
    Two-Way Catalyst
    A catalytic converter that oxidizes hydrocarbons and carbon monoxide, but has little effect on oxides of nitrogen.
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