JK 23112

1. Costco is top-tier gasoline. Of course, they do not have their own refineries.......but likely use Shell, BP/Amoco or what not.

2. All gasoline is the same - but the additives may differ from brand to brand.

3. Octane is the most important thing when a high-performance vehicle such as a Corvette.

4. You can find information about Top Tier Gasolines ( http://www.toptiergas.com ) and see where you can buy it in your region.

5. Shell does seem to be the most popular for people whose cars need premium fuel - but it seems to come at a price. Buying it on Tuesday here lets you save twenty cents a gallon.

JoesC5

I only use Top Tier gas(Phillips 66 and Conoco locally) and ethanol free when I can find it(I can buy ethanol free gasoline locally from Phillips 66 and Conoco).

Locally E10 91 Top Tier gas is priced the same as E10 91 non Top Tier gas just down the street,

I pay $0.10 gallon more for ethanol free Top Tier gas than what E10 Top Tier gas costs.

I also pay around $0.40 a gallon more for ethanol free Top Tier 93(for my Z06) than ethanol free 91 Top Tier. The reason the ethanol free 93 Top Tier is so much more expensive is that the dealer has to have it trucked in from out of state as the local pipeline terminal does not handle 93 octane. The manager told me he didn't know for how much longer he will be able to sell the 93 ethanol free as his price keeps getting higher and higher and there are so few people that are willing to pay the price.

I burn the ethanol free 93 in my Z06 but I use the much cheaper ethanol free 91 in my supercharged Mercedes and my two vintage Vettes(and my riding mower).

When I'm on a road trip in the Z06 and I find ethanol free premium gas but not from a Top Tier station, I carry a 20oz bottle of Chevron Techton and dump it into the tank before I fill up. That adds the additional additives that the non Top Tier gas is missing.

JK 23112

We cannot buy ethanol-free gasoline around here -- unless you go to a marina.

Going outside the Richmond metro area means that some gasoline might cost a bit less because it might be a non-reformulated blend....but it's still E10.

JoesC5

Go to pure-gas.org and click on maps and then zoom in on VA. You can find few gas stations selling ethanol free gas but it appears that most of them are not selling ethanol free premium(a few are).

LDB

Three points about gas from a person who knows, having worked as a chemical engineer in the refining business for a career. Point #1, while true in some parts of the country, it is not true in other parts of the country to say that the basic gas before additives is all the same. If you are near a major refining center such as Houston, LA, Chicago, New Orleans, etc, or are close to a refinery of the brand that you are buying, you are probably getting gas made in that company’s refinery. If you are far from any refineries, you are indeed probably getting common gas out of a pipeline that may or may not be from that company’s refinery. Since the specs of all gas are similar, the difference is not huge. But odds that you will get a bad batch are lower from a major, reliable refiner. So if you are near a refining center, there’s a small, but not totally trivial advantage to buying from a major brand even before you consider the additives.

Point #2, differences in additives are real and non-trivial. I’ve seen 50,000 mile engines torn down after running top tier versus non-top-tier gas, and the difference in cleanliness of injectors, valves, piston crowns, spark plugs, etc, are visually obvious.

Point #3, while I also oppose ethanol in gas as being economically dumb, and a boondoggle supported jointly by Democrats who incorrectly think it helps the environment and Republicans playing footsie with the red state farm lobby and billionaire ethanol plant owners, there are no performance-related reasons to pay more than 3% extra for “pure” gas. That 3% extra is because you will get about that much more mileage, but other than that small mileage difference, there are no other reasons to avoid ethanol for cars built after 1990. Pre 1990 cars, boats, chainsaws and mowers, the situation is a bit muddier, but even there, differences are not huge.

Millerrock

Shell and if I can't find it I will use Sunoco. I never use additives but I do use eth remover before I store it for the winter.

vbdenny

The places listed in Virginia that sell non-alcohol gasoline are distributors for racing fuels (something like 108 octane) which they sell for around $8 a gallon. Never found a alcohol free gasoline in Virginia. I used mainly Costco 93 but on the road, Sunoco, Gulf, Chevron, BP, Shell and Velaro are all Top Tier. I prefer Sunoco as they are the official fuel of NASCAR.

JoesC5

How do they do a "backwash" of fuel in the LT1 and LT4? The intake opens on the downstroke, and closes on the upstroke, and the cylinder is building compression, close to the top of the stroke, the injector forces gasoline into combustion chamber(the intake valve is closed or it would not hold compression) and then the plug is fired. The intake valve stays closed on the power stroke, and then the exhaust valve opens on the upstroke.

For the backside of the intake gas to be "washed" with raw fuel, the injector would have to pulse during the downstroke while the intake valve is open. Since the rush of air entering the cylinder pass the intake valve is pretty powerful, the injector would have to get the gas it pulsed into the cylinder to buck the incoming air pass the intake valve into the intake port and then do a 180 so it could wash the back side of the intake valve. Then there is the additional pressure from the supercharger that is forcing air pass the intake valve on the LT4, that would buck any gas from flowing in the opposite direction.

If it's that simple to do(backwash the intake valve), then why is Ford, Toyota, Lexus, VW, Audi, and Subaru going to the expense of adding additional port injectors to their DI engines to do the same thing(wash the back of the intake valve with raw gas)?

JoesC5

Reference your point #1. My pipeline terminal is in Brookline MO and I buy both Conoco and Phillips 66 gas, so I'm probably getting my gas from their refinery in Ponca City, OK. But, there are a bunch of other refineries around there, so who really knows where my gas comes from(other than the Mexican food I had for dinner).

Reference your point #3. True that I'm paying a little more(~ 4%)for ethanol free gasoline, but I'm getting approximately 5% better fuel economy vs E10. Since it's essentially a wash in cost, I'm supporting my retailer by buying his ethanol free premium, and that means he will still be selling it to me to put in my two vintage Vettes and my lawn mower. If I stop buying his ethanol free premium and go to his competitor and buy their E10 premium for $0.10 a gallon cheaper, then when I want to fill my two vintage Vettes or my mower with ethanol free gasoline, it won't be available, as the original seller will have converted to E10 premium to stay in business.

VETTEKEDC7

I have used Chevron only since the C6. Never have had any fuel system problems, so I continue using it in the C7. Since it has Techron, as does Texaco, I've always relied on that fuel.

LDB

The cited article implies that either some of the gas is injected prior to the intake valve closing or the person writing the article is an idiot. My guess would be the former, since GM is apparently cooperating by furnishing some of the input information. While I do not have first hand knowledge, I have also heard from other second hand sources that some DI engines inject some of the fuel, particularly at low power settings, prior to intake closing. This would presumably happen near bottom dead center, when the rush of intake gases would be reduced, hence late closing of intake valve giving at least a bit of backwash.

I see your point and am sympathetic to it since I don’t like ethanol in gas either. But since ethanol free is comparatively rare, it tends to be a small, niche operation rather than a volume business. Most small niche operators are honest and ok, but the fraction of shady, fly by night operators is higher than for the major brands. A big warning flag in my mind would be if the pump is just marked ethanol free premium, and is not marked with the brand name of the station selling it. That would pretty strongly imply that it is from a less reputable operator and does not have top tier additives. If the ethanol free pump is marked with the station’s brand, then two people must be shady for you to have a problem: both the jobber trucking it in, and the station owner for marking it with the main station’s brand.

JoesC5

I don't buy unbranded gas, period. On the road, I'll buy branded Top Tier E10 before I'll buy any unbranded gas. If I'm forced to buy unbranded(or run out of gasoline in the middle of Nowhere, UT) then I'll add a bottle of Techron to the tank(I carry a bottle with me, but so far, never had to use it on the road). I buy Top Tier ethanol free gasoline when I can and Top Tier E10 otherwise. On a recent vacation to Deadwood, SD, only once did I have to buy E10 premium(at a Mobil station in Deadwood). One tankful in 2,500 miles of driving through four states. The other six fill ups were at Top Tier stations like BP, Cenex, Shell, Phillips 66 and Conoco that sold ethanol free premium.

The availability of ethanol free Top Tier premium varies greatly on which states I'm traveling in. Some states all I can buy is E10 premium, but it will be from a Top tier station.

Luckily, locally I can buy 91 ethanol free and 93 ethanol free Top Tier gasoline, so my vintage Vettes and my lawn mower loves me.

I'm not a bit concerned about pulling into Top Tier stations like Conoco, Shell, etc and their premium gas is ethanol free. All gas sold at a Top Tier stations has to be Top Tier, thus they can't be selling an off brand gas at one pump and Concoco, Shell, etc at the other pumps.

"TOP TIER™ fuel marketers use TOP TIER™ for all octane grades of gasoline sold at their stations. So all grades provide enhanced cleaning power."

"The fuel marketer cannot select only certain service stations to be TOP TIER™ certified. All stations under a licensed fuel marketer’s brand name or franchise name must use the specified TOP TIER™ additives and detergency treat rate"

Ted Cruz once said he would get rid on the ethanol mandates, but that was before he was knocked out of the primaries. Haven't heard a word from Trump about his feelings on ethanol. Hope he dumps the mandates and lets the free market decide what gasoline people want to buy or not buy. Personally, if the oil companies are given the choice, I bet ethanol free 100% pure gas will be cheaper than E10 gas at the pump.

roadbike56

I use Shell. Ethanol free is available, but it's not a top tier brand and they won't say what additives are in it. So I go with Shell.

JoesC5

The ethanol free you mentioned.. that is from another station and not the Shell station. Correct?

Foosh

The midwest is apparently about the only place where ethanol-free gas is still widely available, other than from unbranded dealers and marinas. I've checked the MD locations where it's supposedly available per the ethanol-free website, and they are virtually all unbranded and in very rural areas. There are a very few branded stations which have one pump "around back," and it's always 87 octane. A few sell "racing fuel" at $8/gallon.

That website is also badly out of date because I've called a number of the stations listed, and many are either no longer in business, or no longer sell it.

JoesC5

Pure-gas.org depends on the public to monitor the stations listed

If you see a station that is not accurately listed on pure-gas.org, you can alter the listing or even delete the station from the list.

If a station near you adds ethanol free gas to their pumps, you can add that station to pure-gas.org and specify if it's unbranded or name the brand, the octane(s) that is/are ethanol free, etc

Same as if a station near you changes what they sell.

Pure-gas.org is only there to help the public find gas stations that sell ethanol free gasoline. It is a service to those that are interested in buying ethanol free gas. It only works if the public monitors the stations around them. Pure-gas.org does not call all 11,000 stations on their website everyday to see if they are still selling 91 octane Conoco gas, or 87 octane unbranded gas, or 89 octane branded gas, etc. LOL.

How about helping out others and if you see a discrepancy in a pure-gas.org's listing, correct it and stop bitching about how bad Pure-gas.org is.

They are only trying to help those of us that do want to buy ethanol free gas whenever possible. I personally find the website very useful and I monitor the stations near me. It's impossible for me to monitor the stations near you.

Foosh

You ought to see someone about that burr you have stuck . . .

JoesC5

You ought to pull your head out of your....

There is a convenience store chain in New York and Vermont named Stewart's Shops that has 335 stores and over 200 of them sell ethanol free premium gasoline.

While they are not a branded store they are far from a crappy old service station selling crap gas out back.

If they were selling crap gas out of a pump out back, they wouldn't be as successful a business as they are.

So much for your false statement about ethanol free gas only being available in the Midwest.

Tell me; have you ever driven outside of Maryland? From your posts, it doesn't seem that you have.

I've driven my Corvettes in 40 of the lower 48 plus others in non Corvettes. I do know a little about what is available outside of Maryland.

Foosh

Wow, that useful info, thanks. There are a lot of rural areas in New York and Vermont, which I did include in addition to the midwest. Of course, you'd have to read to have noticed that.

You won't find ethanol-free gas in major population centers other than perhaps the midwest. I also don't see Stewart's Shops on the Top Tier fuel list, and I saw you said above, that's all you purchased. I'm sure their ice cream is probably good.

Saw, your edit. You really are a major piece of work. Ignore button going on, and I suggest you do the same for me. I have no further interest in seeing anything you have to say.

LucaBrasiAZ