Ready for a science class? Here’s something a little different. This is a guest post by Mr. Credit Card from www.askmrcreditcard.com. Today, Mr. Credit Card is going to be talking about the difference between regular and premium gasoline and why you may actually be paying more for your gasoline than you think.
All gasoline is a combination of many different hydrocarbon molecules, ranging from heptane (seven carbon atoms and 16 hydrogen atoms) to decane (10 carbon atoms and 22 hydrogen atoms) and beyond. But the stuff we get from gas pumps is the hydrocarbon identified as octane. The octane number you see at the pump is not actually a measure of the percentage of octane in the gas itself but rather, measures how that gasoline compares with a pure mixture of octane and heptane.
What is an Octane Rating?
Octane, by definition, is the resistance to burn (e.g. detonation resistance) in a car engine. A higher rating means that the gasoline will burn slower when it is ignited in the engine. Therefore, for high compression engines, a higher rating of octane means that there is better control over the gasoline burning. So the goal for every consumer or car owner should be to choose the right octane level or rating for their car engine’s design so that their car’s consumption of gasoline is done with maximum fuel efficiency (and hopefully cleaner emission).
Image from Cagle.com
But to understand this whole concept of matching fuel type to engine, we must first understand the concept of “knock”. “Knock” is the explosion that takes place in the car engine that’s described as an “unregulated explosion”. It happens when the compression of fuel and air in your engine sets off an undesired explosion; when this happens, you’ll hear a loud noise that’s bad for your engine.
Should You Use Regular or Premium Gasoline?
So what type of fuel should you choose for your vehicle? Well it really depends on your engine, and more likely depends on when your car was manufactured.
Older Engines: Older engines use carburetors to regulate air/gas mix. Unlike modern engines which use computers and sensors, an old engine cannot accurately regulate air and gasoline levels consistently. Therefore, carburetors need adjustments during a car’s regular maintenance to ensure that they keep the proper air and gasoline proportions as specified. When adjustments are not made on a regular basis, too much fuel will be mixed with air and the gasoline that does not burn gets turned entirely into carbon deposits. To solve this problem, you could turn to using higher octane or premium gasoline to prevent the “knocking” in your engines.
Newer Engines: Modern engines use fuel injectors with computers to accurately control the air/fuel mix under all temperature levels and in any environment. However, the accuracy of the fuel injectors and computers is based on using the recommended gasoline for that engine, which depends on the engine’s compression ratio. Hence, to make sure that the fuel injector computers work properly, you’ll have to use the right type of fuel.
Most car engines are built and designed to burn regular unleaded fuels with an octane rating of 87 (i.e. regular). High performance sports cars (or higher performance cars) have higher compression ratios and need higher octane (e.g. premium 89 or 92) to avoid knocking.
If your vehicle needs a higher octane rating of 89 to 93, you should find this documentation in the owner’s manual, as well as possibly under the fuel gauge and by the fuel fill hole. Usually you will see this rating for high performance engines only.
To find out what type of gasoline to use, check your owner’s manual. Using premium gasoline isn’t going to help your engine if all you need is regular unleaded gasoline. The bottom line is to use the type of gasoline recommended for your engine. This may help you to trim gas costs.
There have been lots of other posts discussing numerous ways to save money on car expenses. Examples include buying fuel efficient cars and avoiding gas guzzlers. There’s the debate about whether to buy new or used cars (used cars are a great deal). You could also lower your car insurance rates by choosing to own a Honda Civic rather than a BMW convertible. These are choices every car owner has to make based on his or her lifestyle and finances. But I’ve found that many folks assume that paying for “premium gasoline” will “prolong the life of their car engine”.
In some cases, you have to use “premium gasoline”. In many cases, “regular gasoline” will do. The point is, if you don’t know which type of gas you should use, then you might just end up paying a lot more for fuel in the long run. And that is really throwing money away. In addition to using the correct type of gasoline for your car, you should also try these other money-savvy moves: use a gas credit card or a cash back credit card that pays more than 1% on gasoline purchases so you can save money in the long haul.
Copyright © 2010 The Digerati Life. All Rights Reserved.