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- Definition: The capability of the valves, ignition system, and other engine-driven parts of a vehicle to work together for maximum efficiency.
- Importance in Internal Combustion Engines:
- Valves: For optimal performance, the intake and exhaust valves must open and close at precise moments during the engine’s cycle. Proper valve timing ensures that the air-fuel mixture enters the combustion chamber and exhaust gases are expelled at the correct times.
- Ignition System: The spark must occur at the right moment to ignite the air-fuel mixture in the combustion chamber. This precise moment is known as ignition timing.
- Essential Factors:
- Fuel: Correct timing ensures that the fuel is delivered to the combustion chamber at the optimal moment.
- Air: Proper air intake timing ensures that the air mixes with the fuel efficiently.
- Proportion of Mixture: Accurate timing helps maintain the right air-fuel ratio for combustion.
- Compression Timing: Ensures that the mixture is compressed to the right level before ignition.
- Spark: The timing of the spark plug firing is critical for efficient combustion.
- Valve Timing:
- When the piston is in the compression stroke, both intake and exhaust valves must be closed to ensure proper compression.
- If one or more valves are open, the valve timing is out, often due to issues with the timing belt or timing chain jumping a tooth.
- Ignition Timing:
- The spark must occur at the correct moment in the combustion cycle. If it is slightly off, the engine’s efficiency will decrease.
- Ignition timing is checked and adjusted using a timing light and by adjusting the distributor.
- Consequences of Incorrect Timing:
- Poor engine performance
- Decreased fuel efficiency
- Increased emissions
- Potential engine damage
Proper timing ensures that all these elements work in harmony, leading to efficient engine performance and longevity.
See Related Terms:
- Basic ignition setting
- Basic ignition timing
- Basic timing
- Camshaft Timing
- Dynamic ignition timing
- Electronic spark timing
- Engine timing
- Exhaust timing
- ignition timing
- Mechanical ignition timing
- Port Timing
- Reed valve induction timing
- Static ignition timing
- Static timing
- Valve timing
- Variable valve timing