Understanding the names of car parts can be incredibly helpful, whether you’re a seasoned mechanic or just starting to learn about automobiles. Knowing the correct terminology allows for clearer communication when discussing repairs, seeking advice, or even just understanding more about how your vehicle works. This list breaks down some common car part names to expand your automotive vocabulary.
Essential Engine Components
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Power Valve: Primarily found in carburetors, particularly Holley four-barrel models, the power valve is designed to enrich the fuel mixture during periods of high engine load or when the throttle is opened wide. This additional fuel helps to prevent engine knock and provides extra power when needed for acceleration or climbing hills.
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Return Spring: This is a crucial safety component of the throttle mechanism. The return spring is responsible for automatically closing the throttle when your foot is removed from the accelerator pedal. This ensures that the engine returns to idle and prevents the vehicle from continuing to accelerate unintentionally.
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Closed Chamber: Referring to the combustion chamber design in some cylinder heads, a closed chamber is the area within the cylinder head directly above the piston where combustion takes place. This design is known for promoting efficient combustion and often contributes to higher compression ratios.
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30 Over: This is automotive jargon, especially in engine rebuilding, indicating that a cylinder bore has been machined to be 0.030 inches larger than its standard size. “Overbores” are typically performed to repair cylinders that are worn, damaged, or to accommodate larger pistons.
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Deck: The deck of an engine block is the top surface where the cylinder heads are bolted. It’s a critical sealing surface that must be perfectly flat to ensure a proper seal between the engine block and the cylinder head, preventing leaks of coolant and combustion gases.
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Hemi: “Hemi” is short for hemispherical combustion chamber. This design is characterized by a dome-shaped combustion chamber and valves that are positioned at an angle on opposite sides of the chamber. Hemi engines are known for their efficient airflow and high power potential, though they often have more complex valve trains.
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Runner: In the intake manifold, runners are individual passages that channel the air-fuel mixture from the plenum to each cylinder’s intake valve. The design and length of runners can significantly impact engine performance, affecting factors like torque and horsepower at different engine speeds.
Emission and Ventilation Systems
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CCV Valve (Closed Crankcase Ventilation Valve): The CCV valve is an emissions control component that manages blow-by gases. Blow-by occurs when combustion gases leak past the piston rings into the crankcase. The CCV valve recirculates these gases back into the intake manifold to be burned in the engine, reducing harmful emissions and preventing pressure buildup in the crankcase.
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EGR (Exhaust Gas Recirculation): The EGR system is another emission control technology. It works by recirculating a portion of the engine’s exhaust gas back into the intake manifold. This diluted intake charge lowers combustion temperatures, which in turn reduces the formation of nitrogen oxides (NOx), a major air pollutant.
Ignition System Advances
- COP (Coil-Over-Plug): COP ignition systems represent a modern advancement in ignition technology. Instead of using a single ignition coil and distributor to generate and distribute spark, COP systems utilize individual ignition coils mounted directly on top of each spark plug. This eliminates the need for spark plug wires, providing a more direct and efficient spark, often leading to improved engine performance and reliability.
Fuel Injection Differences: Throttle Body vs. Multi-Port
Understanding fuel injection systems is crucial for modern engine technology. There are key differences between Throttle Body Fuel Injection (TBI) and Multi-Port Fuel Injection (MPFI):
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Throttle Body Fuel Injection (TBI): TBI is an earlier form of fuel injection that is often compared to a carburetor in its function. In a TBI system, one or two fuel injectors are located in the throttle body, above the intake manifold. Fuel is injected into the incoming air stream as it enters the intake, much like a carburetor sprays fuel into the air. This system is simpler but generally provides less precise fuel distribution to each cylinder.
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Multi-Port Fuel Injection (MPFI): MPFI is a more advanced and efficient fuel injection method. In an MPFI system, each cylinder has its own fuel injector located in the intake runner, very close to the intake valve. This allows for highly precise fuel delivery directly into each cylinder’s intake port. MPFI results in better fuel atomization, more even fuel distribution, improved fuel economy, and enhanced engine performance compared to TBI.
In summary, knowing these car part names and understanding their functions can greatly improve your understanding of automotive mechanics and empower you to communicate effectively about vehicle maintenance and repair.
