[Z06] All 93 Octane isn't the same
Thread Starter
Instructor
Joined: May 2007
Posts: 165
Likes: 0
From: Miami Florida
All 93 Octane isn't the same
I filled up on RaceTrack 93 octane gas and started having gas gauge problems. My gauge would go to empty and the read out would say 'low fuel.'
I read all the threads on gauge problems and found the answer to my problem. Man I love this forum. Basically, too much sulfur in the gas causes gauge issues. Chevron with techron is the cure.
The lesson I learned was that I should spend the extra 10 cents on quality fuels from Chevron, Shell, etc.
I read all the threads on gauge problems and found the answer to my problem. Man I love this forum. Basically, too much sulfur in the gas causes gauge issues. Chevron with techron is the cure.
The lesson I learned was that I should spend the extra 10 cents on quality fuels from Chevron, Shell, etc.
Team Owner
Joined: Mar 2007
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From: Right Corner Pocket of Illinois
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Problem for me is the closest station is 281 miles away in Kentucky, I use Shell. 
Melting Slicks
Joined: Sep 2005
Posts: 2,568
Likes: 264
From: Near Charlotte NC
You are so right.I like BP( Amoco),Shell,Texaco or Citgo.I stay away from the no-name brands.
To me gasoline is another very important car fluid.Only the good stuff for my Z,S2K & GST.
\db2
Carolina
To me gasoline is another very important car fluid.Only the good stuff for my Z,S2K & GST.
\db2
Carolina
Race Director
Joined: Nov 2000
Posts: 17,103
Likes: 39
From: stop the fun suckers
I think GM recommend top tier gas (its my understanding that top tier gas suppliers are stations that agreed to meet requirements outlined by GM, BMW and some other manufacturer.. ). take a look for yourself..
i think the website is www.toptiergas.com
Top Tier Detergent Gasoline
TOP TIER Detergent Gasoline is the premier standard for gasoline performance. Six of the world's top automakers, BMW, General Motors, Honda, Toyota, Volkswagen and Audi recognize that the current EPA minimum detergent requirements do not go far enough to ensure optimal engine performance.
Since the minimum additive performance standards were first established by EPA in 1995, most gasoline marketers have actually reduced the concentration level of detergent additive in their gasoline by up to 50%. As a result, the ability of a vehicle to maintain stringent Tier 2 emission standards have been hampered, leading to engine deposits which can have a big impact on in-use emissions and driver satisfaction.
These automakers have raised the bar. TOP TIER Detergent Gasoline help drivers avoid lower quality gasoline which can leave deposits on critical engine parts, which reduces engine performance. That’s something both drivers and automakers want to avoid.
i think the website is www.toptiergas.com
Top Tier Detergent Gasoline
TOP TIER Detergent Gasoline is the premier standard for gasoline performance. Six of the world's top automakers, BMW, General Motors, Honda, Toyota, Volkswagen and Audi recognize that the current EPA minimum detergent requirements do not go far enough to ensure optimal engine performance.
Since the minimum additive performance standards were first established by EPA in 1995, most gasoline marketers have actually reduced the concentration level of detergent additive in their gasoline by up to 50%. As a result, the ability of a vehicle to maintain stringent Tier 2 emission standards have been hampered, leading to engine deposits which can have a big impact on in-use emissions and driver satisfaction.
These automakers have raised the bar. TOP TIER Detergent Gasoline help drivers avoid lower quality gasoline which can leave deposits on critical engine parts, which reduces engine performance. That’s something both drivers and automakers want to avoid.
TOP TIER Detergent Gasoline Retailers
Gasoline retailers must meet the high TOP TIER standards with all grades of gasoline to be approved by the automakers as providing TOP TIER Detergent Gasoline.
In addition, all gasoline outlets carrying the brand of the approved retailer must meet the TOP TIER standards.
Additional gasoline retailers are added to the TOP TIER list as they meet the standards. The retailers known to be on the TOP TIER list are shown below.
TOP TIER Gasoline Retailers:
QuikTrip
Chevron
Texaco
MFA Oil Co.
Conoco
Phillips 66
76
Entec Stations
Shell
The Somerset Refinery, Inc.
Kwik Trip / Kwik Star
Aloha Petroleum
Tri-Par Oil Co.
Turkey Hill Minit Markets
Mileage Stations
Chevron Canada
Shell Canada
Petro-Canada
Sunoco Canada
Gasoline retailers must meet the high TOP TIER standards with all grades of gasoline to be approved by the automakers as providing TOP TIER Detergent Gasoline.
In addition, all gasoline outlets carrying the brand of the approved retailer must meet the TOP TIER standards.
Additional gasoline retailers are added to the TOP TIER list as they meet the standards. The retailers known to be on the TOP TIER list are shown below.
TOP TIER Gasoline Retailers:
QuikTrip
Chevron
Texaco
MFA Oil Co.
Conoco
Phillips 66
76
Entec Stations
Shell
The Somerset Refinery, Inc.
Kwik Trip / Kwik Star
Aloha Petroleum
Tri-Par Oil Co.
Turkey Hill Minit Markets
Mileage Stations
Chevron Canada
Shell Canada
Petro-Canada
Sunoco Canada
Last edited by Z06_BluByU; Oct 11, 2008 at 11:06 PM.
Pro
Joined: Sep 2006
Posts: 608
Likes: 259
From: Louisiana
In my parts it doesn't matter where you get the gas, it depends on where the station buys its gas from. When a local refinery had a high sulfur content, virtually all of the stations from Chevron to Exxon to Shell and mom and pop had the bad gas, they all just had different additive packages in them.
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Brett Foote
Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
In my parts it doesn't matter where you get the gas, it depends on where the station buys its gas from. When a local refinery had a high sulfur content, virtually all of the stations from Chevron to Exxon to Shell and mom and pop had the bad gas, they all just had different additive packages in them.
fuel is fuel. Go to the lowest price highest volume stations to get the freshest fuel
additives are like a few drops in a 10K gallons, so top teir or not it does not matter.
My choose here in the Carolinas and Virginia is Hess.
Burning Brakes
Joined: Apr 2007
Posts: 1,030
Likes: 1
From: Douglasville Ga
Anybody ever hear of the quote...You get what you pay for. You pay for the cheapest stuff and usually its the cheapest for a reason. Everytime I put gas from the local QT in my truck (regular mind you) it starts sputtering very badly under low acceleration. I am not OCD about which gas I put in, but if I can help it I put Shell in. When we tore my brothers LS1 down for a heads job, the vavles were spotsless. All he ever puts in it is Shell so that what I try to stick with.
Drifting
Joined: Apr 2000
Posts: 1,390
Likes: 35
From: INDIANA
Well, I'm not sure you can trust any of them all the time. I've bought Amoco Ultimate 93 octane for my modified watercraft for years, increased compression requires it, and they don't have knock sensors. 
Years ago I damaged an engine from not really having 93 oct in the cut rate stations gas. Anyway, Amoco Ultimate is advertised as Clearly Ultimate, because it has no dye in it and you always know you have the real thing, its clear. Last week at a BP mart, with Amoco gas, my Ultimate was yellow/green, "CLEARLY NOT ULTIMATE". I imformed the attendant for what that was worth, but also wrote to Amoco. Makes you wonder.
Years ago I damaged an engine from not really having 93 oct in the cut rate stations gas. Anyway, Amoco Ultimate is advertised as Clearly Ultimate, because it has no dye in it and you always know you have the real thing, its clear. Last week at a BP mart, with Amoco gas, my Ultimate was yellow/green, "CLEARLY NOT ULTIMATE". I imformed the attendant for what that was worth, but also wrote to Amoco. Makes you wonder.
Pro
Joined: Jun 2008
Posts: 583
Likes: 0
From: Philly region SCCA
I started having this problem about 2 weeks ago, but now it's gone. I almost always use Amoco (I guess it's BP now). I've never seen a Chevron, ever, and I'm not sure there are any shells in my area either.
Pro
Joined: Oct 2000
Posts: 666
Likes: 0
From: Oviedo FL
Well, I'm not sure you can trust any of them all the time. I've bought Amoco Ultimate 93 octane for my modified watercraft for years, increased compression requires it, and they don't have knock sensors. Years ago I damaged an engine from not really having 93 oct in the cut rate stations gas. Anyway, Amoco Ultimate is advertised as Clearly Ultimate, because it has no dye in it and you always know you have the real thing, its clear. Last week at a BP mart, with Amoco gas, my Ultimate was yellow/green, "CLEARLY NOT ULTIMATE". I imformed the attendant for what that was worth, but also wrote to Amoco. Makes you wonder.
Years ago I damaged an engine from not really having 93 oct in the cut rate stations gas. Anyway, Amoco Ultimate is advertised as Clearly Ultimate, because it has no dye in it and you always know you have the real thing, its clear. Last week at a BP mart, with Amoco gas, my Ultimate was yellow/green, "CLEARLY NOT ULTIMATE". I imformed the attendant for what that was worth, but also wrote to Amoco. Makes you wonder.I use it solely in my Z and MS3. I've never had any fuel gauge issues with it.
Instructor
Joined: Jul 2008
Posts: 176
Likes: 0
From: Bangor ME
Here in Maine it doesn't matter what station it is - you're getting fuel from the Irving Refinery in St. John, NB. This is probably the case in a lot of places. The only thing that distinguishes them is the additives. Gas is gas, but a lower budget station always has more risk of getting some water or debris in the fuel.
Burning Brakes
Joined: Jul 2003
Posts: 904
Likes: 36
From: Santa Cruz CA
Same but different.
Sadly in CA where I am I know our 93 is different..it's only 91 octane, /sigh.
Ok past that I admit to not knowing how the the whole fuel distribution system works. I heard that the major local refineries make up the base fuels then they get an 'additive' spike depending on the type of brand.
So Shell distribution trucks or Chevron distribution trucks would all have their own blend even though they are all using the same base product.
And that the low buck stations where low buck because they would get straight base product, no rust inhibitors or seasonal blends or cleaning agents etc, therby making the gas cheaper. Also I think the additive blends are patented in the case of like Techron and such. I have been using Valero around here because I heard its just rebranded Shell and the Shell station is halfway across town.
Ok past that I admit to not knowing how the the whole fuel distribution system works. I heard that the major local refineries make up the base fuels then they get an 'additive' spike depending on the type of brand.
So Shell distribution trucks or Chevron distribution trucks would all have their own blend even though they are all using the same base product.
And that the low buck stations where low buck because they would get straight base product, no rust inhibitors or seasonal blends or cleaning agents etc, therby making the gas cheaper. Also I think the additive blends are patented in the case of like Techron and such. I have been using Valero around here because I heard its just rebranded Shell and the Shell station is halfway across town.
Team Owner
Joined: Mar 2007
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From: Right Corner Pocket of Illinois
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St. Jude Donor '12 thru '26
Last week my Cousin tried to convince me to use the 100 octane low lead aviation fuel at his airport. I didn't see any reason to so I declined. I figured the computer would have to re-learn and it might not be good for the cats. I'll stick with Shell 93 and an occasional jug of Techron, that combo has been good to me so far.
Pro
Joined: Sep 2006
Posts: 608
Likes: 259
From: Louisiana
Melting Slicks
Joined: Dec 2006
Posts: 2,186
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From: Woodinville WA
In WA our highest octane is 92. But some gas contains 10% ethanol. I stay away from the gas with alcohol b/c you get less power and lower mileage so the cheaper price they sell it for is a wash anyway. Alcohol per volume produces about half the power of gas so in a 10% solution you'll get roughly 5% less power. It may not seem like much, but on a 500hp motor you'll be down 25hp, and some people spend thousands on trying to gain 25hp.
Team Owner
Joined: Sep 2003
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From: Raleigh / Rolesville NC
Tech Contributor
Joined: Oct 1999
Posts: 41,044
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From: Charlotte, NC (formerly Endicott, NY)
It doesn't matter in my area either. There are none of those stations within a reasonable driving distance of where I live. the closest Shell Station may be 100 miles away in New Jersey. I use Mobil from the neighborhood station. They usually have the cheapest or next to cheapest prices anyways.
Bill
Bill