First Gear: What is this?

by Sam Sweet

Definitions for terms or acronyms or abbreviations about or for cars that are frequently mentioned.

ABS- Most modern cars have ABS, Anti-lock Braking Systems, which is where brake force is adjusted to prevent the wheels from locking up.

Boost pressure- The increase above atmospheric pressure used in turbocharging and supercharging.

Catalytic converter- A device using metals similar to and including palladium that chemically reacts with certain emissions from the exhaust and makes them into less harmful to the environment.

Crankshaft- A metal rod with cranks that attach to the pistons and turn their reciprocal motion into rotary motion.

Differential- The special gearbox that splits the incoming torque between the driven wheels.

DOHC- Double OverHead Camshafts. Simply a term that describes an engine with two cams per cylinder rather than one.

Driveshaft- The shaft that transmits power to the differential from the transmission.

ECU- Engine Computer Unit. Literally the computer system that controls the engine.

Exhaust manifold- The system of tubes that collects exhaust gas from the cylinders and moves it toward the catalytic converters and muffler.

Intake manifold- The system of tubes that puts the mixture of fuel and air into the cylinder.

LSD- Limited Slip Differential. A type of differential that limits the maximum difference in speed and torque between each wheel, ensuring both wheels always get some power.

Mid-Engined- a setup where the engine is behind the passengers but ahead of the rear axle. Helps center of gravity and handling improve.

Oversteer- When the back wheels are ahead of the front.

Redline- The maximum revolutions per minute an engine can handle.

Supercharger- A device that allows for more air intake than the engine can do alone. Creates engine drag, as it is powered by the crankshaft.

Transaxle- A differential and transmission combined

Turbocharger- An air compressor that uses an exhaust-driven turbine

Understeer- Where the front wheels don’t turn sharply enough, not enough angular momentum to turn.