What Does Car Compression Ratio Mean?
2 Answers
Car compression ratio refers to the ratio between the maximum volume of the cylinder at the bottom dead center and the minimum volume at the top dead center during the compression stroke. Methods to check a car's compression ratio include: the vehicle's user manual, the manufacturer, or a 4S dealership. The compression ratio is an important parameter for measuring a car engine's performance. A higher compression ratio results in greater vehicle power, more complete combustion, fewer emissions, but also requires higher-octane gasoline. The purpose of the car compression ratio is to inform the owner which grade of gasoline should be used. The gasoline grade does not indicate its cleanliness but rather which type of car (with a specific compression ratio) it should be used for.
As an experienced driver who has driven many cars, the compression ratio is a key figure for me when it comes to how the engine works. Simply put, it's the ratio of the space in the cylinder when the piston is at the bottom to when it's at the top. For example, a compression ratio of 10:1 means that when the piston pushes down, the air and fuel mixture is loose, and when it pushes up, it compresses tightly, resulting in a more powerful ignition burst. High-compression-ratio engines are more powerful and accelerate faster, like those sporty cars, but the downside is that they require more expensive 95-octane gasoline. Otherwise, the mixture may detonate prematurely under high compression, causing knocking sounds that can damage the engine. I always check this parameter when buying a car because it affects fuel consumption and driving experience. Choosing the right one makes long-distance driving both fuel-efficient and comfortable.
