fnbrowning

The Florida Department of Agriculture and Consumer Services regularly conducts inspections of the petroleum distribution system and analyzes samples of petroleum products to ensure consumers are being offered quality products at a fair measure. During the 2010/2011 fiscal year 97.9 percent of the samples collected and analyzed from more than 10 billion gallons of petroleum fuel distributed throughout Florida met state standards, which are considered among the strictest in the nation.

Sam's Club premium gasoline, while not containing the same type of additive package as a Top Tier dealer, does certainly contain the fuel system additives and octane content required by law.

It does absolutely no harm to run Sam's Club gasoline for your refills, as long as you do refill at a Top Tier dealer occasionally, as it recommended that all drivers switch gas dealers to take advantage of different cleaning packages.

JoesC5

Here in Springfield, MO we have Conoco selling 91 and 93 octane with 0 ethanol and two Phillips 66 stations with 94 octane ethanol free gas, both are Top Tier. We also have some Signal stations with 91 octane ethanol free gas but they are not a Top Tier gas.. I get about 1.5 MPG better gas mileage when I'm running 0 ethanol gas and can really tell the difference in how my Z06 runs with the 94 octane vs. the 91 octane, especially during the hot summer months.

JoesC5

Or run a 20 oz bottle of Techron through the system every 4-5,000 miles. I use only Top Tier Conoco and Phillips 66 gas but run a bottle of techron through my Z06 and my supercharged mercedes once a year. When I go to San Antonio to visit my parents, I use other Top Tier brands, to mix up the additive package like you mention.

fnbrowning

Just HAD to tell us about the 94 Octane didn't ya?
I think I saw those stations on the Ethanol-free gas stations site. http://pure-gas.org/
Do keep it updated as needed.

Of course you got better MPG w/o ethanol, as ethanol is a scam!

Wayne O

I prefer 'name' brand fuel usually from a top tier supplier. That said I don't think it's always essential to buy "TopTier" fuel. Just because an oil company isn't a member of a club doesn't mean their fuel is substandard. I think it's more likely at a deep discount retailer but you can get 'bad' fuel anywhere. It happens on occasion.

CITGO? CITGO is a subsidiary of Petróleos de Venezuela S.A., the Venezuelan state-owned petroleum company, a US incorporated firm refiner and marketer of gasoline and other petroleum products. DO NOT BUY FROM CITGO and support Hugo Chavez and his anti-American policies! We need a new government. On one hand they preach independence from foreign oil but they do everything possible to restrict exploration and the utilization of our own energy assets.

LDB

Actually, that’s not true, or at least not true enough to worry about. Octane is set by hydrocarbon types, like aromatics, olefins, paraffins, and if applicable, the added ethanol. To change octane, an aromatic would have to change into a paraffin, or some similar thing. That simply doesn’t happen to any significant extent at room temperature over even lengthy periods in storage. Having said that, there still is reason to prefer fresh gas. The reasons just aren’t octane. Lighter components can evaporate, such that the vapor pressure is too low for proper cold starts. Moisture can condense, which is ok as long as the station properly purges their water draw boot, but could be a problem if they don’t. And additive packages can degrade with lengthy storage. So I agree with preferring fresh gas. I’m just quibbling a bit with the reasons for that preference. Also, on the mid grade, I’d say sometimes rather than usually, about it being a pump blend of regular and premium. Trouble is, octane doesn’t blend linearly, so for example, if you blended 2 parts 87 with 1 part 93, you wouldn’t end up with exactly 89. So if a station does mid grade by pump blending rather than an actual third tank, they have to over blend a bit. You can tell by going to the manhole covers where they drop off shipments. Count the covers versus the number of grades being offered (be sure to count diesel as a grade if the station offers diesel). Usually the number of covers will match number of grades offered, so usually, there is not pump blending of mid grade.

Larry/car

Currently, in the North East we are getting the winter fuel mix. I personally don't notice any power loss but the fuel mileage decreases about two miles per gallon. There are times when I have gotten a tank of fuel that just doesn't seem to make normal power and the mileage is lower as well. Could it be the octane is lower and the computer adjusted engine parameters to burn the fuel? It has happened many times and is not brand specific.

LDB

The big difference in winter fuel is more butane for higher vapor pressure to help cold weather starts. Since butane contains less energy per gallon than base gasoline, mileage drops. But there should not be any issues that would affect power. If they did not add the extra butane in winter, you'd have difficulty starting the car on cold mornings.

Larry/car

I always wondered what was added and why the mileage drop. Aviation fuel never changes and the aircraft are hard to start when it gets cold.

Z06LUST

The LS7 is BUILT and TUNED by GM to run on 93. It will run safely (west coast) on 91 but at some hp loss. (93-94 no difference)

The OP is asking about the LS3 which is tuned for 91. So any LS3 owners 'jealous' over the 94 availability...don't fret--if your running a stock tune it would be a total waste of money and do nothing for you in terms of performance/power.

LDB

Agree, and would add that knock sensors give you about 4 octane worth of wiggle room where they trade off less power and mileage for the lower octane. So for base coupe and Grand Sport, with design 91, you are protected by knock sensors down to 87 at reduced power/mileage. For Z06/ZR1, with design 93, you are protected down to 89 at reduced power/mileage. You’re in danger of serious engine damage below 87 with coupe/GS, and below 89 with Z06/ZR1. Unless you have modded the engine, there is no benefit to octane over 91 with coupe/GS, or over 93 with Z06/ZR1. If you’re at high altitude like Denver or Santa Fe, knock 2 off all of the above numbers.

Rocket-J

We do have 100 octane here in Northern Cal. One brand is VP.We have Valero Gas here that is from the US. I think I heard it was from Texas. Thats almost U.S.

Radioman

Yeah but, Exxon/Mobil is a Top Tier Gas...but that's another thread in itself

BadAV

PM me the addresses of those stations if you don't mind. My daughter is in school in Springfield so I'll want to fill up at one of them sometime and try them out. We can't get anything in St. Louis except 10% ethanol.

need-for-speed

Can't argue with that. Unicorn milk and rainbow dust just doesn't get it done.

I only stop at Sh!tgo to use their bathroom.

florida john

Enjoy your Citgo gas from Hugo Chavez (Venezuela's despot)! Citgo is owned by Venezuela to market their gas. I have heard that Hess shares a refinery with them in the Carribean, but can't verify that.

Difference between the fuels is in the additives, but what you would sense would be the result of octane. Octane is posted at the pump. and Sams near me have 93. Shouldn't feel any difference.

incabird

Over at Costco the other day I noticed they have their gas advertised as containing five times the minimum amount of government required aditives. It seems to run well in my daily driver and I have used the 93 in the Vette a time or two and it ran well in it also.

Marc V.

OK guys. I retract posting the list including Citgo. I am aware of Citgo's position.

With that being said, I still only use Sunoco Ultra 93.

fnbrowning

Go to: http://pure-gas.org/index.jsp

JoesC5

Just wish I could get the 94 octane ethanol free gas outside of Springfield. I've tried to use the puregas.org to locate stations when I'm traveling, but have had little luck as they are always way out of my way. There is a station in Fayetteville, AR selling 94 octane ethanol free Sunoco but I never have any reason to go there.