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DPDT

An acronym for double pole double throw.

DPFE

A Ford term Differential pressure feedback EGR or Delta pressure feedback EGR.

DPH

Dual plug head.

DPI

Dual plug inhibit.

DPS

Differential pressure switch.

DPST

An acronym for double pole single throw.

DPVS

Distributor ported vacuum switch.

DQ

An acronym for disqualified.

DQSDTE

(Porsche) Air Quantity across the Idle air control valve (IACV).

DRAC

An acronym for Digital Ration Adapter Controller, Used by the microprocessor to change analog signals to digital signals.

Draft

To follow another vehicle close enough to take advantage of the slipstream or partial vacuum created behind it at very high speeds.

Draft Tube

A vent to release engine-crankcase vapors.

Drafting

The technique of following another vehicle closely to save fuel.

Drag

1. A performance term for a quarter-mile race from a standing start, against time or another car. 2. An acceleration contest between two vehicles. 3. The resistance of air against an object trying to pass through it.

Drag Coefficient

A term used for coefficient of drag.

Drag Coefficient

See coefficient of drag.

Drag Link

The steering component that connects the Pitman arm to the steering arm.

Drag Race

A form of straight-line speed competition that is run on a drag strip. Drag races are either run heads-up or as a handicapped bracket race.

Drag Racing

An acceleration contest between two vehicles.

Drag Racing

See drag race.