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Flash Gas

Gas resulting from the instantaneous evaporation of refrigerant in a pressure-reducing device, such as an expansion valve.

Flash Point

The lowest temperature at which a flammable liquid produces sufficient vapor to flash near its surface, but without continuing to burn.

Flash To Pass

A steering-column-mounted dimmer switch having an additional feature that illuminates the high-beam headlights even with the headlight switch in the OFF or PARK position.

Flashback

A recession of the flame back into the mixing chamber of the oxy-fuel gas torch or flame-spraying gun.

Flashback Arrester

A device to limit damage from a flashback by preventing propagation of the flame front beyond the location of the arrester.

Flasher

An automatic-reset, circuit-breaker-type switch used in directional signal and emergency signal circuits.

Flat Four

An opposed four-cylinder engine.

Flat Motor

A Ford flathead V-8. Also known as a flatty.

Flat Out

Full throttle.

Flat Rate

A method of charging for services based on the time normally required to perform a particular service.

Flat Six

An opposed six-cylinder engine.

Flat Spot

The momentary loss of power as engine speed is increased.

Flat Spot

A term used to describe two very different conditions. One has to do with tires

Flat Tappet

A mechanical valve lifter.

Flat Tow

To tow a vehicle on all four wheels.

Flat Track

A dirt oval track without banked turns.

Flat-panel Lcd

A type of LCD monitor commonly used in entertainment systems and navigation systems. The best flat screens offer a wide viewing angle, so they can be seen clearly by people who are not sitting directly in front of the monitor.

Flathead

An engine having intake and exhaust valves in the block.

Flathead

An engine block design with the intake valves and exhaust valves located in the block, rather than in the cylinder head. The head is literally a flat slab that sits on top of the block. By far the most famous flathead is the Ford V8 engine produced from 1932 through 1948. The flathead Ford was one of the first engines for which performance parts were made, and it remains popular among street rod and custom car enthusiasts today.

Flattie

See flatty.