Glossary “four valve” Definition:
Four valves, two intake and two exhaust, per cylinder.

Glossary “four valve head” Definition:
Head design having four valves per cylinder.

Glossary “four wheel alignment” Definition:
Method of wheel alignment done on many newer cars that are equipped with rear wheel alignment capability.

Glossary “four wheel drift” Definition:
Controlled four-wheel slide on a paved surface.

Glossary “four on the floor” Definition:
Four-speed manual transmission with a floor-mounted shift lever.

Glossary “four point seat belt” Definition:
A safety-belt system with two shoulder straps, two lap straps, and a single buckle.

Glossary “four speed” Definition:
Manual transmission with four forward gears.

Glossary “four cammer” Definition:
V-type engine with dual overhead camshafts on each cylinder bank.

Glossary “four corners scuffing” Definition:
Damage to the piston that usually occurs as a result of an external cause, such as too lean an A/F mixture, which causes the top of the piston to run too hot.

Glossary “four cycle” Definition:
Term used for four-stroke cycle.

Glossary “four cycle engine” Definition:
Combustion ocurrs every other revolution of the crankshaft; a cycle being considered as 1/2 revolution of the crankshaft. These cycles or strokes are: (1) intake stroke, (2) compression stroke, (3) power stroke, (4) exhaust stroke. Also known as Otto cycle engine.

Glossary “four gas analyzer” Definition:
Exhaust gas analyzer able to detect and measure exact amounts of HC, CO, CO2, and O2.

Glossary “four by” Definition:
Term used for 4×4.

Glossary “four banger” Definition:
1). A four-cylinder engine. 2). Vehicle equipped with a four-cylinder engine.

Glossary “four barrel carburetor” Definition:
Carburetor having four ventures.

Glossary “four bolt mains” Definition:
Main bearing cap that is held in place with four bolts.