Random Tips: The Truth on Gas

As if living in Hawaii isn't expensive enough, not only did our general excise tax increase, but our gas increased 11 cents on the start of the new year. You can read more at Aloha Update, another blog I write for on the increase of gas prices.

Anyway, I recently had an opportunity to talk to a big time engineer who works at one of the large gas companies, and decided to tap into his head about the truth on gasoline. As you already know, I like to save gas particularly because with a few pointers, you can actually save a lot of money. I've already wrote two articles on saving gas, which can be found at this link, and this link. Anyhow, here is what he had to say.

Grades of Gasoline
So I asked him what's the benefit of having midgrade, or 89 octane, gasoline? No cars ask that the minimum octane level should be 89...most say the car needs a minimum of 87 or 91 octane. He reported two reasons.

1. Psychologically, people think 89 is better than 87 because it has a higher octane number. Partially true, but not quite. People think 89 is better because they think it is a cleaner gas and/or will help your car engine run cleaner and smoother. All is false, except the last point, which is semi-true. A higher octane gas does not clean your engine better...the cleaning agents are due to the additives, which is normally added in all grades. If you car only requires 87 gas, putting in 89 won't make your engine cleaner. For the most part, it won't even make your car run smoother, unless you have a very old car. This leads to the 2nd point.

2. He added that the ONLY time you ever need to use grade 89 gasoline is if you have a really old car, and the car starts knocking. The engine may need a higher octane to reduce the knocking due to the compression ratio. If 89 doesn't get rid of the engine knocking, you will be forced to use 91 octane and above. Most cars these days have knock sensors that prevent knocking if a lower octane is used, so you shouldn't experience knocking at all. Since that is the case, using 89 octane will not help your car at all. Only two octanes are needed, 87 and 91.

Additives
I wrote about additives in my previous article Tips to Save Gas in point number 1. I wanted to know how important these additives are, and if they really do what they are supposed to do, which is keep your engine clean. This is what he had to say.

The additives are important because they really do clean your engine. Examples are Chevron's Techron and Shell's V-Power. BUT, it is NOT NEEDED EVERYTIME. This means, you DON'T have to put in gas with these cleaning additives everytime you fill up. It won't hurt your car if you do, but also isn't necessary to put it in so frequently. He told me that you only need to use these types of gas every once in a while. For example, you can put in gas from Costco or other gas stations, then every month or two, put in gas from the big companies such as 76, Shell, Chevron, etc. This will ensure that your car engine will stay clean, AND you will save big bucks by not using big gas companies which usually charge more than others.

Conclusion
1. Use the type of gasoline your car manual asks for. If it's 87, only put in 87. If it's 91, put in 91 (or higher...some places have 92). There is no sense putting in 89, unless your car engine starts knocking...but the chances of that are very slim due to knock sensors. Putting in 89 octane normally is a waste of money.

2. Octane levels do nothing more than prevent your car from knocking. Cars with higher compression ratios need higher octanes...these are usually high end sport cars or luxury cars...all of which normally have really high horsepower. Then again, a Corvette only takes 87 octane gas. That Honda Civic you drive definitely won't need 91 octane gas. Octane level does not correlate to a cleaner running engine. Instead, putting in the correct octane will save you money if your car only requires 87 octane gas.

3. Additives do clean your engine, but you do not need to fuel your car with expensive fuel everytime. This means you can fill your car at Arco for the most part, then every month or two, depending on how often you drive, fill in gas from 76, Shell, or Chevron. This will save you money by purchasing cheaper gas for the most part, but keeping your engine clean every month or two.