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Blow Torch

A jet-powered car for drag or lake competition.

Blowby

Byproducts of combustion, mostly hydrocarbons, that leak out of the combustion chamber, past the piston and piston rings, into the crankcase during the compression and power strokes. In modern engines, blowby vapors are drawn into the intake through the positive crankcase ventilation (PVC) system and are burned in the engine.

Blowby

Leakage of unburned fuel and gases past the pistons and down into the crankcase. Blowby is often the result of poorly fitted or excessively work piston rings. Blowby contaminates the engine oil. On some vehicles, a PCV valve is used to recycle blowby back through the intake system.

Blower

Slang for supercharger or turbocharger.

Blower Belt

A reinforced cover with retaining straps on supercharged engines, required by NHRA to prevent parts from scattering should the supercharger explode

Blower Circuit

All of the electrical components that are required for blower and blower speed control.

Blower Motor

An electric motor and squirrel cage type of fan moving air inside the vehicle for heating, cooling, and defrosting.

Blower Motor Relay

A relay found in the blower circuit.

Blower Relay

An electrical device used to control the function or speed of a blower motor.

Blower Speed Controller

A solid-state control device that operates the blower motor and, sometimes, the compressor clutch based on signals from the microprocessor.

Blower Switch

A dash-mounted device that allows the operator or turn the blower motor ON/OFF and/or to control its speed.

Blown Engine

1. An engine that has a supercharger or turbocharger. 2. A seriously damaged engine.

Blown Head Gasket

A broken head gasket that leaks water, oil, or air and reduces engine performance.

Blowoff Valve

A part of most turbocharger systems. The blowoff valve opens when the driver lifts off the throttle, allowing boost to bleed out of the system. Without a blowoff valve, the boost would try to flow back up into the turbocharger, causing compressor surge.

Blowout

A tire explosion. A tire-monitoring system is designed to help prevent blowouts by keeping tabs on tire pressures and temperatures.

Blu

Blue.

Blue Book

A term given the Kelly Blue Book, a bimonthly publication that lists used car wholesale and retail prices.

Blue Oval

A reference to the Ford logo.

Blue Smoke

An exhaust produced when oil has contaminated the air/fuel mixture.

Blue Streak

The trade name of a Goodyear high-performance tire.