Automotive terms Modern (B)

Automotive Technical terms and abbreviations overview used in the industry, Guide and explanations.

The following are examples of Mid Modern technical terms recommended for general use worldwide. For in-depth specific terms also see terms for historic vintage and specific areas such as Paint.

BACKFIRE:
The sudden combustion of gases in the intake or exhaust system that results in a loud explosion.

BACKLASH:
The clearance or play between two parts, such as meshed gears.

BACKPRESSURE:
Restrictions in the exhaust system that slow the exit of exhaust gases from the combustion chamber.

BACKUP CAMERA:
Often fitted to large vehicles and on modern cars to aid reversing.

BAKELITE:
A heat resistant, plastic insulator material commonly used in printed circuit boards and transistorized components.

BALANCED VALVE:
A valve that is positioned by opposing auxiliary hydraulic pressures and/or spring force. Examples include mainline regulator, throttle, and governor valves.

BALL AND SOCKET
A mechanical linkage ball joint commonly used in suspension and steering.

BAND:
A flexible ring of steel with an inner lining of friction material. when tightened around the outside of a drum, a planetary member is held stationary to the transmission/transaxle case.

BALL BEARING:
A bearing made up of hardened inner and outer races between which hardened steel balls roll.

BALL JOINT:
A ball and matching socket connecting suspension components (steering knuckle to lower control arms). It permits rotating movement in any direction between the components that are joined.

BARO (BAROMETRIC PRESSURE SENSOR):
Measures the change in the intake manifold pressure caused by changes in altitude.

BAROMETRIC MANIFOLD ABSOLUTE PRESSURE (BMAP) SENSOR:
Operates similarly to a conventional MAP sensor, reads intake fold pressure and is also responsible for determining altitude and barometric pressure prior to engine operation.

BAROMETRIC PRESSURE:
pressure on the Earth's surface caused by the weight of the air in the atmosphere

BALLAST RESISTOR:
A resistor in the primary ignition circuit that lowers voltage after the engine is started to reduce wear on ignition components.

BATTERY:
A direct current electrical storage unit, consisting of the basic active materials of lead and sulfuric acid, which converts chemical energy into electrical energy. Used to provide current for the operation of the starter as well as other equipment, such as the radio, lighting, etc.

BEAD:
The portion of a tire that holds it on the rim.

BEARING:
A friction reducing, supportive device usually located between a stationary part and a moving part.

BEFORE TOP DEAD CENTER (BTDC):
The point just before the piston reaches the top of its travel on the compression stroke.

BELTED TIRE:
Tire construction similar to bias-ply tires, but using two or more layers of reinforced belts between body plies and the tread.

BELL HOUSING
Portion of the transmission bolted to the engine block sometimes separate fitting that allows the same transmission to be used on multiple engines.

BENCH SEAT
A full width front seat often on early cars with dash column change

BEZEL:
Piece of metal surrounding radio, headlights, gauges or similar components; sometimes used to hold the glass face of a gauge in the dash.

BIAS-PLY TIRE:
Tire construction, using body ply reinforcing cords which run at alternating angles to the center line of the tread.

BI-METAL TEMPERATURE SENSOR:
Any sensor or switch made of two dissimilar types of metal that bend when heated or cooled due to the
different expansion rates of the alloys. These types of sensors usually function as an on/off switch.

BLOCK:
Engine Block large main part of engine. Often made of steel or aluminium.

BLOW-BY:
Combustion gases, composed of water vapor and unburned fuel, that leak past the piston rings into the crankcase during normal engine operation. These gases are removed by the PCV system to prevent the buildup of harmful acids in the crankcase.

BOOK TIME:
Term for costs Labor Time on repair.

BOOK VALUE:
The average value of a car, widely used to determine trade-in and resale value.

BOOST VALVE:
Used at the base of the regulator valve to increase mainline pressure.

BORE:
Diameter of a cylinder.

BRAKE
This is the tearm used for slowing or stopping a moving vehicle.

BRAKE CALIPER:
The housing that fits over the brake disc. The caliper holds the brake pads, which are pressed against the discs by the caliper pistons when the brake pedal is depressed.

BRAKE BIAS (BALANCE)
Distribution of brake force at the front and rear often set more to front on disc-drum brakes set up.

BRAKE FLUID
Used to amplify braking force hydraulic brakes a type of hydraulic fluid on modern cars replaing cable systems.

BRAKE HORSEPOWER (BHP):
The actual horsepower available at the engine flywheel as measured by a dynamometer.

BRAKE FADE:
Loss of braking power, usually caused by excessive heat after repeated brake applications.

BRAKE HORSEPOWER:
Usable horsepower of an engine measured at the crankshaft.

BRAKE PAD:
A brake shoe and lining assembly used with disc brakes.

BRAKE PROPORTIONING VALVE:
A valve on the master cylinder which restricts hydraulic brake pressure to the wheels to a specified amount, preventing wheel lock-up.

BRAKE SHOE:
The backing for the brake lining. The term is, however, usually applied to the assembly of the brake backing and lining.

BREAKER POINTS:
A set of points inside the distributor, operated by a cam, which make and break the ignition circuit.

BRINNELLING:
A wear pattern identified by a series of indentations at regular intervals. This condition is caused by a lack of lube, overload situations, and/or vibrations.

BTDC:
Before Top Dead center. often used for timming

BUCKET SEAT
contoured car seat often with deep sides and used for sports cars sometimes with no recline function.

BULLBAR
A device installed on the front of a vehicle often in rural country’s now outlawed in some places due to safety concerns.

BUMPER
Often integrated or external fitted on early cars to the front and rear ends of a vehicle, to absorb some impact in a collision.

BUMP:
Sudden and forceful apply of a clutch or band.

BUSHING:
A liner, usually removable, for a bearing; an anti-friction liner used in place of a bearing.

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