Engine tuning

Engine tuning is an adjustment, modification of the internal combustion engine, or modification to its control unit, otherwise known as its ECU (Engine Control Unit). It is adjusted to yield optimal performance, to increase an engine's power output, economy, or durability. These goals may be mutually exclusive, and an engine may be detuned with respect to output (work) in exchange for better economy or longer engine life due to lessened stress on engine components.

It has a long history, almost as long as the development of the automobile in general, originating with the development of early racing cars, and later, with the post-war hot-rod movement. Tuning can describe a wide variety of adjustments and modifications, from the routine adjustment of the carburetor and ignition system to significant engine overhauls. At the other end of the scale, performance tuning of an engine can involve revisiting some of the design decisions taken at quite an early stage in the development of the engine.

Setting the idle speed, fuel/air mixture, carburetor balance, spark plug and distributor point gaps, and ignition timing were regular maintenance items for all older engines and the final but essential steps in setting up a racing engine. On modern engines, equipped with electronic ignition and fuel injection, some or all of these tasks are automated, although they still require periodic calibration.

A tune-up usually refers to the routine servicing of the engine to meet the manufacturer's specifications. Tune-ups are needed periodically as according to the manufacturer's recommendations to ensure an automobile runs as expected. Modern automobiles now typically require only a small number of tune-ups over the course of an approximate 250,000-kilometre (160,000 mi) or a 10-year lifespan.

Tune-ups may include the following:

In early days, mechanics finishing the tune-up of a performance car such as a Ferrari would take it around a track several times to burn out any built-up carbon; this is known as an Italian tuneup.

Modern engines are equipped with an engine management system (EMS)/Engine Control Unit (ECU) which can be modified to different settings, producing different performance levels. Manufacturers often produce a few engines which are used in a wider range of models and platforms, and this allows the manufacturers to sell automobiles in various markets with different regulations without having to spend money developing and designing different engines to fit these regulations. This also allows for a single engine to be used by several different brands, tuned to suit their particular buyer's market.

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Wikipedia