Boxer Engine (used by Subaru, Porsche/RUF)

The banks of cylinders are arranged in a horizontal formation that makes the engine flat. It provides a very low center of gravity and an aerodynamic profile. Most engines in road cars today come in two configurations. The V has two banks of cylinders arranged in a V shaped engine block. This is the most common configuration for six, eight, ten and twelve cylinders engines. Hence, the references to V-6, V-8, V-10 and V-12 cylinder engines. Another common configuration is the in-line configuration. The cylinders are arranged in a single row in the engine block and is most common with 4 and 6 (older) cylinder engines. Also sometimes called a flat 4, 6, 8, 10 or 12.

VTEC Valve System (used by Honda/Acura cars)

Variable Valve Timing and Electronic Lift Control. Changes intake and exhaust valve timing and lift so that it more closely matches the engine's changing air-fuel needs. The result is maximum torque at all engine speeds and under all driving conditions.

Variable Valve Timing (used to Toyota and now Mazda)

Engine valves can be adjusted to create higher fuel-to-air ratios. The higher the ratio, the bigger the explosion that drives the engine and thus more power.

ROTARY ENGINE (mostly used by Mazda)

This is a rotary internal combustion engine perfected by Felix Wankel during the 1950s and 60s. This engine has two-thirds less moving parts than the traditional piston-powered engine used in all diesel and gasoline engines sold in America. Oddly enough, power is derived from an almost triangle-shaped rotor spinning within an almost oval housing. The advantages are very smooth operation, more reliability than a standard piston engine and greater ability to utilize multiple fuels in the future.

Inline Engine

Configuration where all cylinders are in a single row. Most common in four-cylinder engines, but there are currently high performance six-cylinder (BMW, Lexus), economy-three cylinder (Suzuki), and low vibration five-cylinder (VW, Audi and Volvo) engines in modern cars.

Normall Aspirated Engine

Sometimes called a "free breather." An engine where all the air to the cylinders is not forced in, as with turbo chargers or super chargers.

Turbocharger

A performance-increasing turbine positioned in the exhaust system. Expanding exhaust gases spin an impeller (very small fan-type blades) at speeds up to 25 thousand rpm, driving a similar compressing impeller. Compressed air from the driven impeller is forced into the induction system, which squeezes more air/fuel mixture into the combustion chambers. With the greater charge of air and fuel, a more powerful combustion burn results, thus more power. The big advantage of the turbo over directly driven superchargers is the increased efficiency, although there is a slight lag before the turbine spins up and increases the power output. Originally turbos were developed to enable aircraft to fly at high altitudes, then they found use in diesel trucks and train engines to increase their torque.

Supercharged Engine

An engine that is similar to a turbocharged engine which uses a series of belts or chains from the crankshaft to turn the turbines that forces the air/fuel mixture into the cylinder heads under pressure creating a bigger explosion which generates more power. A turbocharger use the exhaust gases to turn the turbines to create the same effect.