Glossary of Terms
D
The dealer in South Gate, California, known for transplanting 427ci big-block V-8s into first-generation Camaros.
Decamber (Verb) --The act of making the wheel camber more negative.
Deck --A rearmost upper body panel of a car that is not present in all cars.
Deck Height --The distance measuring the area between the top of a piston at its outermost edge and the surface forming the head/block interface of the block.
Deck Lid --The door to the area (often the “trunk”) beneath a deck.
Differential --A gear assembly that reduces the rotational velocity transmitted from the engine/gearbox and also divides the driving force to two wheels. The gear assembly is separate from the transmission.
Differential Housing --Housing where differential/final drive gears are mounted.
Disc Brake --A braking system where friction between a pad and rotating disk are needed to providing braking force for the wheel.
Dish --A curved-in or concave piston crown.
Displacement (Engine) --In a reciprocating engine, Displacement refers to the swept volume of one cylinder times the number of cylinders. In a rotary engine, Displacement refers to the difference between the largest and smallest volumes of the working chamber, times the number of lobes, times the number of rotors.
Distributor Cap --A part containing high voltage distributor contacts and a way of securing high voltage wires.
Dome --An outwardly-curved or convex piston crown.
Door Panel --An inner part of the door that supports the trim.
Driver Belt --When attached by pulleys to a rotating part of the engine, such as the crankshaft, the Drive Belt (which is a reinforced elastomer band) has the potential to provide the driving force for the engine accessories.
Drive Shaft --The mechanical drive train coupling between transmission and differential. By using universal, constant velocity, or flex joints, the Drive Shaft allows an angular displacement of the driving and driven axes.
Drive Train --Those parts in a car producing and conveying driving power to the ground, as well as any housing containing these components.
Dry Sump --A system of engine lubrication in which residual lubricant is pumped by a “scavenge pump” to an external storage tank. From here an additional pump or pumps provide a supply of pressurized lubricant from the storage tank to the engine.
Dry Tire --A race car designed specifically for racing under dry conditions. This type of tire often has grooveless tread, and because of this, should not be used in any conditions other than dry.
Dryer (AC) --A part within the automotive air conditioning system that removes water from the refrigerant.
Dual Quads --Is a description a carburetion system that consisted of two four-barrel carburetors on a single intake manifold.
Dust Shield --A cover that protects parts of the disc brake assembly from mud, dirt, etc.
DZ302 --A DZ302 was a small-block Chevrolet engine that was used exclusively in 1967 --
1969 in Z28 Camaros. The used a short 3.00-inch-stroke crank from the 283 with the 4.00-inch bores of the 327 for homologation for the SCCA Trans Am Race Series. These engines developed 290 horsepower. The Trans Am Race rules restricted the Trans Am Race Cars to 305 cubic inches or less.
