Air-fuel ratio: The amount of fuel mixed with air for combustion. Too much fuel is considered running "rich", while too little fuel creates a "lean" condition.

Alloy: Metal product composed of two or more metals mixed to produce desired attributes. Commonly found in wheels and other lightweight, strong components.

Axle-back exhaust system: Any exhaust system that replaces the midpipe, muffler, tailpipe, and exhaust tip.

Bezel: The rim of an instrument (gauge) that holds the glass or plastic lens in place.

Adjustable cam gears: Add-on component that allows independent adjustment of cams for proper timing in a modified engine.

Camber: A term used to describe the angle of the wheels against the ground. Zero degrees camber results in the wheels being perpendicular to the ground. A positive camber setting indicates the wheel is leaning out at the top, while with negative camber the wheels will lean in.

Camber kit: An accessory that allows precise adjustment of camber, especially helpful for correcting camber in lowered vehicles.

Cat-back exhaust system: An performance exhaust system that replaces all factory exhaust components behind the catalytic converter.

Chip: Short for a performance upgrade that involves replacing the car's original factory engine management program with a hi-performance version. Usually accomplished by opening the ECU and replacing a plug-in computer chip.

Coil-over spring: A shock with an integral spring. Most upgrades feature adjustable spring perches which allow the ride height of the car to be raised and lowered easily.

Cold-air intake: An intake system that draws cold air from outside the engine compartment.

Control arm: A hinged suspension component that connects the wheel hub to the vehicle's frame.

Dubs: Slang for wheels with a 20" diameter.

Fiberglass Body Kit: The original body kit material, fiberglass is lightweight, inexpensive, and easily repaired.

FRP: Short for fiberglass reinforced plastic

Hid light: A lamp that produces light when electricity excites a gas-filled bulb element. Requires a ballast to operate.

JDM: Short for Japanese Domestic Market.

L.E.D. lighting: Accent lighting kits that use Light Emitting Diodes to produce light. LED's are bright, efficient, and quick to react, making them a perfect choice for a wide range of effects.

Mass airflow sensor: A sensor in the air intake that measures the amount and density of air entering the engine for fuel and spark management.

Nitrous injection: Adding Nitrous Oxide to the air-fuel mixture entering a combustion chamber increases the Oxygen content and, combined with additional fuel, produces a significant power increase.

Piggyback ECU: An add-on engine control unit that adds engine performance and functionality without disrupting factory control of non-performance oriented engine systems.

Polyurethane or Urethane body kit: Constructed of the same materials as factory bumper covers, polyurethane body kits are lightweight and flexible, but cost more than traditional fiberglass kits.

Ride-height: Height of the vehicle off the ground. Adjustable with a coil-over strut package.

Rims: Wheels

Short-ram intake: An aftermarket intake system that draws air from inside the engine compartment.

Spring rate: The amount of force needed to compress a spring. Typically measured in pounds/inch, or kilograms/centimeter.

Strut tower bar: A chassis stiffening bar attached between upper strut mounts to improve handling.

Supercharger: A belt or gear driven air pump that forces more air and fuel into the combustion chamber for more power.

Turbocharger: An exhaust-driven air pump that forces more air and fuel into the combustion chamber for more power.

VTEC: (Variable Valve Timing and Lift Electronic Control) A system used in some Honda engines to allow the engine to breathe differently at different RPMs for optimum performance.