Gas (petrol) preferences?

[Dave T]

Nearly every forum has a gasoline discussion!

My feeling is that "gas is (almost) gas". There is little difference in gas. Still, I have favorites.

Gas is the same.
1. In many areas, there are only a limited number of refineries. In Washington state, there are 5 refineries, including one small one. BP/Arco, Shell, Tesoro, and Conoco Phillips/76 are the main four. Chevron sources its gas from Shell or at least they used to. It's part of an agreement where Shell gets Chevron gas for stations in Southern California.
2. There are standards for gasoline.

Gas is not the same.
1. One person working in the industry said that companies keep the "best" gas for themselves and sells the lower quality batches (which still meet the minimum industry standards) to others, calling it rack rate gas.
2. There are claims by the Top Tier gas group where they require higher amounts of additive to reduce engine deposits. However, Top Tier also requires 8-10% ethanol, which some consumers don't like.
3. One Tesoro spokesman once said that they won't put even a penny more per gallon more additives because they thought the consumer will switch brands even to save a penny per gallon.

There is anecdotal reports of gas being the same and not being the same. Gas does age so fresh gas is better.

Chevron said that Techron in a bottle is very similar to Techron in gas, except the bottle form results in a 10 times higher concentration. Therefore, you might be able to "make" your own Chevron like gas by adding 1/10th of a bottle of Techron to ordinary gas.

In a way, I am very compulsive in not mixing brands of gas. I use Chevron almost exclusively. There are two cheaper, high volume Chevron stations. About every 1-2 years, when the tank is nearly empty, I begin to use either 76 or Shell (not both at the same time). The logic is that Shell V-Power might dissolve away any Chevron Techron residue. After several tankfuls of the new brand, I then run the tank to 1/4 full or a bit less (not too little in order not to burn out the fuel pump), then refill with Chevron. Since Shell has a local refinery and not Chevron, maybe I should use Shell most of the time. However, the cheaper, high volume Shell station is inconveniently located. This not mixing gas is really witchcraft and probably borders on crazy behavior. Still, that's what I do.

A bit off topic, Singapore has a huge refining capacity on Jurong Island. It exports refined petrol to other countries, including quite a bit to Australia.

[Shazam]

I pretty much use Valero. It's the cheapest in my town (10 cent discount for using cash), and the guys that run it a very nice, so I like to support them. But other than that, what is closest as I approach E... although I do try to avoid ExxonMobile and now BP (BP isn't very common in NY). Sorry, but I'm a "Gas is gas" guy. Sure they add their own "little something extra special" but I don't think it does much difference.

[nordwulf]

I usually go the major brands like Shell, BP and Mobil. Sometimes I go to the smaller/local gas stations like Holiday or Speedway. Appearance, cleanliness, the age of the gas station, pay-at-the-pump and availability of bucket & squeegee for windows cleaning and paper towels for checking oil/covering the gas nozzle handle are more important reasons for me to choose a certain gas station. Some gas stations like Holiday have pretty good/fresh coffee and that's another reason for me to fill up there with fuel for the car and my body.

Interesting info Dave, I wasn't familiar with most of it.

[euromobile900]

Gas does age so fresh gas is better.

Do you think that fuel stabilizer is any good, or would you consider it yet another form of Snake Oil? I know from experience that old gas in a lawn mower results in the mower being harder to start, but it's not the end of the world. Usually a bit more choke and it's fine. I've used old gas that was treated with the stabilizer when new and it seems just the same as old gas without. I assume that like most things, it was more of a problem 50 years ago, but with new additive technology it must make less difference.

[Shazam]

Do you think that fuel stabilizer is any good, or would you consider it yet another form of Snake Oil? I know from experience that old gas in a lawn mower results in the mower being harder to start, but it's not the end of the world. Usually a bit more choke and it's fine. I've used old gas that was treated with the stabilizer when new and it seems just the same as old gas without. I assume that like most things, it was more of a problem 50 years ago, but with new additive technology it must make less difference.

I added fuel stabilizer to my car before I put it away for storage. Fuel stabilizer is more important for carbureted engines because the small amount of fuel left sitting in the carburetor can degrade and gum up quicker than the large amount left in the fuel tank. Also, when it gums up, it can clog up fuel jets in the carburetor. The fuel in the carb is more open to the air than the big amount that is in the gas tank, and oxygen in the air reacts with the hydrocarbons in the gasoline, which in turn produces a new compound that is... well, gummy. This happens as time progresses. Products like Sta-bil (fuel stabilizers) are meant to prevent this from happening, and keep the quality of gas from degrading.

I've seen sources that say gas starts to degrade (or is noticeably degraded... I can't remember) after about 60 days, or two months time. I occasionally make it about one month or on the same tank of gas... the car seems to run the same at day 30 than it did on day one. The argument that gas is better today because of the newer technology has been battled in posts and sites I've read. Most that disagree with that say, that gasoline is a much more refined, and complex thing that it was say 50 years ago. But because of that, it more easily breaks down into simpler, more stable compounds.

Whose right? I have no idea, but I've seen old gas before, and how it gums up--all that stuff at the bottom, lots of people contribute it to "dirty" gas, but usually it's just oxidized/gum gas. So I paid the five bucks for the little bottle, and added it to my car before driving it to storage just in hopes that it actually does prevent the gas from gumming... I'm not too worried about it not being as effective as a fuel. Will it work? I'll only find out when I go to get the car... if the jets are open, and it starts right up, I'll assume it does.

[jlrSAAB]

Saab recommends no additives on gas,,,,,,, see the quote owner's manual. for high mileage engines about ten years old cars high octane 93mon will help.

For optimum performance Saab recommends: _______________________ AON 90.
Gasoline with a lower octane rating can be used, although not lower than AON 87. However, engine performance will fall slightly and heavy loading and laboring should be avoided. For optimum performance, use the recommended grade of fuel.

Fuel (Gasoline Engine)

Use of the recommended fuel is an important part of the proper maintenance of your vehicle.
For optimum performance Saab recommends:
• Gasoline engines – AON 90.
Gasoline Octane
Use regular unleaded gasoline with a posted octane of 87 or higher. If the octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine. A little pinging noise when you accelerate or drive uphill is considered normal. This does not indicate a problem exists or that a higher-octane fuel is necessary. If you are using 87 octane or higher-octane fuel and hear heavy knocking, your engine needs service.

Additives
To provide cleaner air, all gasolines in the United States are now required to contain additives that will help prevent engine and fuel system deposits from forming, allowing your emission control system to work properly. You should not have to add anything to your fuel. However, some gasolines contain only the minimum amount of additive required to meet U.S. Environmental Protection Agency regulations. Saab recommends that you buy gasolines that are advertised to help keep fuel injectors and intake valves clean. If your vehicle experiences problems due to dirty injectors or valves, try a different brand of gasoline.
Gasolines containing oxygenates, such as ethers and ethanol, and reformulated gasolines may be available in your area to contribute to clean air. Saab recommends that you use these gasolines, particularly if they comply with the specifications described earlier.
Notice: Your vehicle was not designed for fuel that contains methanol. Do not use fuel containing methanol. It can corrode metal parts in your fuel system and also damage the plastic and rubber parts. That damage would not be covered under your warranty.
Some gasolines that are not reformulated for low emissions may contain an octane enhancing additive called methyl cyclopentadienyl manganese tricarbonyl (MMT); ask the attendant where you buy gasoline whether the fuel contains MMT. Saab does not recommend the use of such gasolines.
Fuels containing MMT can reduce the life of spark plugs and the performance of the emission control system may be affected.
The malfunction indicator lamp may turn on.
If this occurs, return to your authorized Saab dealer for service.

[euromobile900]

Well, I'd never put fuel stabilizer in a fuel injected car, but the Tractor currently has some in it, as do the mowers and such. I have never noticed a difference on a fuel injected car, even after gas has been sitting for close to a year. I've taken apart carburetors with jellied gas in them, this is true. Never met any of the varnish stuff though. I think because I am adept at rebuilding carburetors, I don't care as much about fuel stabilizer. But I can see why it gets used for that reason.

[SaabKen]

It's Shell all the way for me. But until (very recently) I was an ardent 87 octane-sometimes-splurge-to-89-or-91 person [guilt].

For the past two months I've been keeping the gal on nothing but 89. Idles better, starts better, better pick-up and smoother acceleration. Slightly better (~ 5-8%) fuel economy too.

[jlrSAAB]

in Spain we have only 95oct ron and 98oct ron gasoline (87mon/90mon in US). I use efitec 98octanes.
I try to avoid the petrol stations near the rivers, they have a lot of water condensation in the tank.

[Shazam]

I think I might have proven myself wrong. On the way to Ohio, I topped the car off with 93 (had 89 in it) and I forgot to take my roof rack off for the long trip, so my average mpg was 21.6. On the way back, I filled it up with 93 and took the roof rack off. I averaged 26.7 mpg. I'm not sure what played a bigger role... more experimenting to be done!