Premium? Regular?

Question

So the car requires Premium, what are the effects of using regular unleaded in a vehicle that requires premium gas.

Answer 1

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.

Answer 2

Compression ratio has little to do with recommended octane rating. For instance the 24 valve Ford Duratec motor used in the Taurus, Sable and the new Ford Fuson recommend 87 octane fuel. The compression ratio is 10.1 in all these motors. I've never herd mine knock under any condition. The shape of the combustion chamber and spark plug placement is the major reason some motors knock and others don't.

The use of 87 in any motor calling for 93 will eventually cause damage to the pistons, top rings, valves and valve seats.

If you're not willing to put the correct gas in your car why did you purchase it to begin with? You paid for a high performance engine now you have to feed it!

Answer 3

It will probably cause knocking in your engine - which is very *bad*. It will probably end up costing you more in repairs than just paying the little extra for Premium, if you use Regular instead of Premium for a period of time.

Answer 4

If its a very new car it'll probably just be slower, older cars you may get pinging and knocking, knocking is VERY bad for your engine and can cause serious damage. When the weather is colder you're more likely to get away with it though, heat makes knocking much worse so in cold weather you can generally get away with a few points lower octane fuel.

Answer 5

The computer/knock sensor in it should reduce your power to prevent engine knock.

The effect is that you won't have as many horses under your right foot as you are used to.

If your computer doesn't do that, you can trash the engine.

Answer 6

gas is gas the only difference is price you can use reg unleaded w/o any ill effects

Answer 7

poor performance and chance of the engine detonating itself to death.

Answer 8

it might cause engine knocking

Answer 9

the answer is there in your question

REQUIRES