ENGINE IDENTIFICATION
It is important for servicing and ordering parts, to know which engine you have. The Vehicle Identification Number (VIN) is visible through the windshield on the driver’s side of the dash and contains data encoded into a lengthy combination of letters and numbers, it can also be located on a driver door or body. A specific letter or number is used to designate the installed engine.

Beginning in 1981, all domestic manufacturers adopted a uniform, 17-digit VIN. The tenth digit of the VIN indicates the model year and the eighth digit indicates the engine code.

ENGINE ASSEMBLIES refer to sets of engine components required to make up a complete automotive engine. Engine assemblies are needed to perform partial replacements, engine swaps and direct engine replacements. A typical packaged engine assembly may include a number of engine parts such as lower blocks, connecting rods, crankshafts, main bearings, rings, rod bearings, pistons, etc.

ENGINE BLOCK is a metal casting that serves as a basic structure on which other engine parts are installed. A typical block contains bores for pistons, pumps or other devices to be attached to it. Even engines are sometimes classified as small-block or big-block based on the distance between cylinder bores of engine blocks. Engine blocks are made from different materials including Aluminum alloys, gray cast iron, ferrous alloys, white iron, gray iron, ductile iron, malleable iron, etc.

ENGINE OVERHAUL kits are prepackaged sets of engine components used to perform major makeovers of automobile engines. Overhaul procedures often entail removing the engine and then rebuilding or replacing its internal parts (pistons, cam shaft, valves, piston bushings, connecting rods, etc.).

THE DIESEL ENGINE
Diesel engines, like gasoline powered engines, have a crankshaft, pistons, camshaft, etc. In addition, four-stroke diesels require four piston strokes for the complete combustion cycle, exactly like a gasoline engine. The difference lies in how the fuel mixture is ignited. A diesel engine does not rely on a conventional spark ignition to ignite the fuel mixture. Instead, heat produced by compressed air in the combustion chamber ignites the fuel and produces a power stroke. This is known as a compression-ignition engine. It is running on combustion chamber heat alone. Designing an engine to ignite on its own combustion chamber heat poses certain problems. For instance, although a diesel engine has no need for a coil, spark plugs, or a distributor, it does need what are known as “glow plugs.” These look like spark plugs, but are only used to warm the combustion chambers when the engine is cold. Without these plugs, cold starting would be impossible. Also, since fuel timing (rather than spark timing) is critical to a diesel’s operation, all diesel engines are fuel-injected rather than carbureted, since the precise fuel metering necessary is not possible with a carburetor.

TURBOCHARGING AND SUPERCHARGING
The word turbocharger is an abbreviation of the word turbo supercharging. Although there is a difference between turbocharging and supercharging, the principle is the same-to drive a small compressor which will increase the quantity of air going into the combustion chamber as it is needed, increasing the volumetric efficiency of the engine and increasing the power output. Supercharging accomplishes this by operating the compressor mechanically, through a gear-driven shaft. The supercharger is normally activated on demand, when the accelerator pedal is pushed to the floor. A turbocharger is actually a small turbine, which uses exhaust gasses to spin a turbine wheel mounted on a common shaft with a compressor. As the turbine turns at high speed, it causes the compressor to pack a greater charge of air into the engine’s cylinders.