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The_Professional
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My dad just bought a car and he decided to use a premium gasoline instead. The car uses regular at the moment, if premium is mixed into it would it somehow ruin the engine? long term wise is this a bad thing?
If you've read How Car Engines Work, you know that almost all cars use four-stroke gasoline engines. One of the strokes is the compression stroke, where the engine compresses a cylinder-full of air and gas into a much smaller volume before igniting it with a spark plug. The amount of compression is called the compression ratio of the engine. A typical engine might have a compression ratio of 8-to-1. (See How Car Engines Work for details.)
The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.
- What is detonation / knock?
Under normal conditions, the combusting air and fuel mixture inside the combustion chamber ignites in a controlled manner. The mixture is ignited by the spark, normally in the center of the cylinder, and a flame front moves from the spark towards the outside of the cylinder in a controlled burn. Detonation occurs when air and fuel that is ahead of the flame front ignites before the flame front arrives because it becomes overheated. Under these conditions, the combustion becomes uncontrolled and sporadic and often produces a pinging noise, or a "knock" noise when the conditions become worse.
So far, detonation sounds cool... why is it bad?
Detonation is definitely not cool. Detonation causes sudden pressure changes in the cylinder, and extreme temperature spikes that can be very damaging on engine pistons, rings, rods, gaskets, bearings, and even the cylinder heads. Even the best engine components cannot withstand severe detonation for more than a few seconds at a time. More severe detonation obviously leads to more severe forms of engine damage. If there is enough heat and pressure in the combustion chamber, detonation can begin to occur before the spark plug even fires, which would normally initiate the combustion. Under these circumstances, known as "pre-ignition", the piston may be traveling up towards a wave of compressed, exploding gas. These are the worst kinds of detonation conditions, and can bend con-rods and destroy pistons.
The answer to this question depends on several factors, including the type of car you have and your personal driving habits. Premium gas generally has a higher octane rating, which can improve performance and fuel efficiency in some cars. However, if your car does not require premium gas, using regular gas will not cause any harm.
No, using regular gas in a premium car will not damage the engine. However, it may result in reduced performance and fuel efficiency.
Yes, you can switch between regular and premium gas without any issues. However, if your car requires premium gas, consistently using regular gas may result in reduced performance and fuel efficiency.
Again, this depends on your car and driving habits. If your car requires premium gas, it is necessary to use it for optimal performance and fuel efficiency. However, if your car does not require premium gas, using it will not provide any significant benefits.
In most cases, using premium gas will not make your car go faster. The higher octane rating in premium gas does not directly increase horsepower or speed. However, in some high-performance engines, using premium gas may result in slightly improved acceleration and performance.