Is premium fuel always "premium"?

[Bob M]

Like many of you, I always put premium fuel in my Vette. I purchase most of the gas for my three vehicles at a local Cumberland Farms (Gulf) Gas Station. One day I decided to fuel up at the neighboring Sunoco Station and put in a tank of "Ultra 93", instead of the usual 92 octane premium at Cumberland Farms. Needless-to-say, there was an obvious change in performance. I now only use Ultra 93 in my Vette.

Could it be the alledged premium fuels at some stations are not the octane they claim to be? My neighbor tells me he uses Shell's "V-power" premium fuel and is very satisfied with the performance. Have any of you experienced anything similar?

Bob

 

[Toms007]

I often wonder this too. It is obvious, to me, that some fuels are just better. I hope someone with some background here can give us some answers.

 

[XLR8]

Bob,

Our newly returned Corvette Guru Paul (c4c5specialist) had this to say about Octane:

Octane is simply the resistance to burning. European formulations are much different, man I wish we had their fuel here.

The fact is that 91 or better is what is recommended for Corvette, LS1 or LS6. This is in your owners manual. Remember, you only need what is specified by your owners manual. Any more is simply a waste of money. Fuel formulations are dictated by the EPA, and must perform certain functions to be sold.

Additives and ethanol, MTBE, and others are only there to reduce emissions, and provide no performance improvements. Ethanol, will actually reduce your mileage per gallon.

As a sidebar, the higher octane you use, the more carbon you will deposit in your combustion chamber. This will also lead to spark knock. This is why 12345515 or Chevron Techron is a recommended fuel systems cleaner, because it will reduce carbon buildup within your engine, and keep spark knock down.

That post is from this thread: Click me

Paul has written extensively on the merits of Techron, the additive in Chevron gasoline. It's also in Texaco gasoline... I suppose there was a merger somewhere back.

At CruiseFest 05 during one of his seminars, he recommended adding Techron to your gas tank occasionally if you weren't able to purchase it from the pump.

Techron by Chevron is also a very good cleaner that GM actually recommends to assist in cleaning the sulfur contamination off the fuel sensor. GM part number is 12345104 for the 20 oz bottle.

That post is from this thread: Click me

Hope some of this helps. You could send a PM to Paul with any other specific questions not covered by my generic answer.

Jane Ann

 

[bossvette]

I use techron in mine and use only Sonoco or Shell unless I am traveling and cannot find it. Yes, gas is mandated to meet Federal standards but the name brands have different additives to clean the fuel system and improve performance. Its the old thing "you get what you pay for" Kind of like the difference between a Blazer and an Escalade either will do the job but the Escalade does it with more style at a higher cost.

 

[Bob M]

One of my buddies use to work for H-Vide Shipping and they transported gas and fuel oil up and down the East and Gulf Coasts. He basically told me all gas is the same when they deliver it, with the exception of the octane levels. Once the brand names get it, they start adding their additives to make it their own blend. He further advised me to buy the cheapest gas that runs well in my cars without loss of performance.

All I know is the Ultra 93 Sunoco made my Vette perform noticeably better than when I was using the premium fuel offered by Cumberland Farms Gulf gas.

It was interesting to read what "Guru Paul" had to say in the above quote.

Bob M.

 

[WNH]

All I know is the Ultra 93 Sunoco made my Vette perform noticeably better than when I was using the premium fuel offered by Cumberland Farms Gulf gas.

I use Sunoco 93 Ultra too, in the Vettes.
I hope its good stuff, but who really knows.
A few years ago, Sunoco Ultra was 94 octane, but they discontinued it and Ultra is now 93 octane.