What is the compression ratio of the Bora engine?
2 Answers
The compression ratio of the Bora engine is 10.5:1. Engine compression ratio: Refers to the degree to which the engine's mixed gas is compressed, expressed as the ratio of the total cylinder volume before compression to the cylinder volume after compression, which is the ratio of the combustion chamber volume. Compression ratio and gasoline octane rating: The engine compression ratio is the most important parameter in determining the appropriate gasoline octane rating. Academically, there is no very unified standard specifying which octane rating should be used for which compression ratio. Moreover, with the widespread application of knock sensors and automatic adjustment technology for ignition timing, high-compression ratio cars can also use lower octane gasoline. Using the correct gasoline not only increases power but also saves fuel, makes the engine run smoothly and quietly, maintains an appropriate engine temperature, and ensures good lubrication.
I drove a Bora for quite a long time, and its engine compression ratio was about 10.5:1, which is quite common, especially for the Bora 1.5L model. Simply put, the compression ratio is the volume ratio before and after cylinder compression. A slightly higher value means more complete combustion, better fuel efficiency, and smoother starts. However, I noticed that the Bora's design prioritizes safety, keeping the compression ratio at this golden point of 10.5 to avoid knocking issues caused by ratios that are too high. Regular 92-octane gasoline is sufficient. Over the long term, the engine noise is minimal, and maintenance isn’t troublesome—just regular oil changes and spark plug checks. Some worry that high compression ratios might harm the engine, but the Bora’s tuning is smart, with a combined fuel consumption of around 6-7L/100km, making it a reliable and balanced choice for a family car.