Best gas?
04-06-2013, 07:54 PM
#16
Rennlist Member
04-06-2013, 09:04 PM
#17
Drifting
Find a gas station with high volume/traffic. If the gas is turned over more frequently at the gas station then there is less time for water to settle in their tank...
Last edited by USMC_DS1; 04-07-2013 at 09:08 PM.
04-06-2013, 10:56 PM
#18
Guys Get the Pure Gas app for your iphone which gives all the locations for ethanol free gas stations except all you poor souls in Cal.
04-06-2013, 11:54 PM
#19
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Correct me if im wrong but isnt shell the only dedicated refinery left? In other words ... anybody e
gas is from where ever butt Shells gas is from their refinery always! Plus according to some reviews their premium is labeled as 93 octane but independently tested to 96? I will dig further for the documentation.....
gas is from where ever butt Shells gas is from their refinery always! Plus according to some reviews their premium is labeled as 93 octane but independently tested to 96? I will dig further for the documentation.....
04-07-2013, 09:35 AM
#20
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The problem is, that most of the enthanol free gas is only 91 octane. I'd rather have the ethanol and the 93 octane. It's become nearly impossible to find 93 octane pure gas. I was able to in 2011. It all ended in early 2012.
04-07-2013, 10:16 AM
#21
Let me preface my reply with the fact that I work for Shell.
There are about 200 refineries left in the US. Not all refineries though actually produce gasoline or even all grades of gasoline. The requirements in California are pretty stringent. That being said any gasoline that makes it to the California market is essentially the same as far as base formulation goes. Clearly, there are more "brands" of stations than there are brands of manufacturing. Which basically means that Joe's Gas Depot could be getting its gasoline from a Shell or a Chevron or a Flying J.
The difference, and it is an important one, is the additives. There's a bit of marketing (Nitrogen Enriched Gasoline) but it is more science and research (Techron and VPower). These additives do help keep gunk from building in the combustion chambers. Will any of us notice a difference over a single tank? Probably not, but over the course of an ownership cycle, I think you would notice the difference between top tier and bottom tier gasoline.
As far as ethanol goes, I don't think gas with 10% will impact performance too much. Considering 25% of all corn that is grown in the US is used to make ethanol for gasoline blending, it is probably here to stay. I don't see any reason for the US to mandate more ethanol (other than corn lobbyists) as the oxygen content required for clean burning is met at 10%. At higher blends, you will lose performance as the combustion value of ethanol is lower than that of gasoline.
So what gasoline do I use - Shell primarily but Chevron as a backup. I have splashed some Exxon in the tank in an emergency.
There are about 200 refineries left in the US. Not all refineries though actually produce gasoline or even all grades of gasoline. The requirements in California are pretty stringent. That being said any gasoline that makes it to the California market is essentially the same as far as base formulation goes. Clearly, there are more "brands" of stations than there are brands of manufacturing. Which basically means that Joe's Gas Depot could be getting its gasoline from a Shell or a Chevron or a Flying J.
The difference, and it is an important one, is the additives. There's a bit of marketing (Nitrogen Enriched Gasoline) but it is more science and research (Techron and VPower). These additives do help keep gunk from building in the combustion chambers. Will any of us notice a difference over a single tank? Probably not, but over the course of an ownership cycle, I think you would notice the difference between top tier and bottom tier gasoline.
As far as ethanol goes, I don't think gas with 10% will impact performance too much. Considering 25% of all corn that is grown in the US is used to make ethanol for gasoline blending, it is probably here to stay. I don't see any reason for the US to mandate more ethanol (other than corn lobbyists) as the oxygen content required for clean burning is met at 10%. At higher blends, you will lose performance as the combustion value of ethanol is lower than that of gasoline.
So what gasoline do I use - Shell primarily but Chevron as a backup. I have splashed some Exxon in the tank in an emergency.
Last edited by Thundermoose; 04-07-2013 at 11:15 AM.
04-07-2013, 11:07 AM
#22
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Chevron premium. Have ran it for years in everything from my wife's ML320 to my Ferrari 348TS. I believe the additive package is the best out there. I have never purchased a tankful of contaminated gas from a Chevron station. I recall running a couple of tanks through a Ferrari 308QV years ago, and observing a real improvment in engine response, idle etc. Techron is a pretty good product, IMHO.
04-07-2013, 12:11 PM
#24
Rennlist Member
Let me preface my reply with the fact that I work for Shell.
There are about 200 refineries left in the US. Not all refineries though actually produce gasoline or even all grades of gasoline. The requirements in California are pretty stringent. That being said any gasoline that makes it to the California market is essentially the same as far as base formulation goes. Clearly, there are more "brands" of stations than there are brands of manufacturing. Which basically means that Joe's Gas Depot could be getting its gasoline from a Shell or a Chevron or a Flying J.
The difference, and it is an important one, is the additives. There's a bit of marketing (Nitrogen Enriched Gasoline) but it is more science and research (Techron and VPower). These additives do help keep gunk from building in the combustion chambers. Will any of us notice a difference over a single tank? Probably not, but over the course of an ownership cycle, I think you would notice the difference between top tier and bottom tier gasoline.
As far as ethanol goes, I don't think gas with 10% will impact performance too much. Considering 25% of all corn that is grown in the US is used to make ethanol for gasoline blending, it is probably here to stay. I don't see any reason for the US to mandate more ethanol (other than corn lobbyists) as the oxygen content required for clean burning is met at 10%. At higher blends, you will lose performance as the combustion value of ethanol is lower than that of gasoline.
There are about 200 refineries left in the US. Not all refineries though actually produce gasoline or even all grades of gasoline. The requirements in California are pretty stringent. That being said any gasoline that makes it to the California market is essentially the same as far as base formulation goes. Clearly, there are more "brands" of stations than there are brands of manufacturing. Which basically means that Joe's Gas Depot could be getting its gasoline from a Shell or a Chevron or a Flying J.
The difference, and it is an important one, is the additives. There's a bit of marketing (Nitrogen Enriched Gasoline) but it is more science and research (Techron and VPower). These additives do help keep gunk from building in the combustion chambers. Will any of us notice a difference over a single tank? Probably not, but over the course of an ownership cycle, I think you would notice the difference between top tier and bottom tier gasoline.
As far as ethanol goes, I don't think gas with 10% will impact performance too much. Considering 25% of all corn that is grown in the US is used to make ethanol for gasoline blending, it is probably here to stay. I don't see any reason for the US to mandate more ethanol (other than corn lobbyists) as the oxygen content required for clean burning is met at 10%. At higher blends, you will lose performance as the combustion value of ethanol is lower than that of gasoline.
One of the best snapshots on the subject I've ever come across. Thank you T'Moose.
04-07-2013, 12:28 PM
#26
Rennlist Member
Does Ultra 94 contain ethanol? Does Petro-Canada still offer an ethanol-free gasoline?
Ultra 94 contains ethanol. Due to the fact that various fuel grades are blended at the point of sale, most grades of Petro-Canada fuel may now contain up to 10% ethanol. This represents a change from the previous state, where premium fuel was ethanol-free at Petro-Canada.
Total BS. Now even 94 has ethanol. I'll send a thank you letter to my local corn farmer lobby.
Shell V-Power 91 octane still doesn't have any ethanol. Maybe I should switch?
04-07-2013, 04:40 PM
#28
Poseur
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Technology comes with some tradeoffs. In the United States we deal with octane numbers that are somewhat confusing. On the pump is the R+M/2 number which is the Research Octane Number (RON) added to the Motor Octane Number (MON) divided by 2. That is, the RON is the octane determined by running the blend in a test engine under controlled conditions, with a variable compression ratio. The MON reflects how the fuel actually performs under a load, and in more expected conditions encountered with a normal automobile in the field. As most of us know, the RON is fairly high and in the USA would be rated at about 97 Octane. The MON would be about 87-88 Octane and so coupled together and divided by 2 we get an Anti-Knock Index (AKI) of 92-93 Octane. California, due to additional additives to keep things cleaner, to include the 10% ethanol), arrives at 91 Octane.
In Germany, the AKI fuels (that concern us with the Carrera) include the Blei-Fri Super e.g., that from Aral which is called SuperPlus 98 and Aral Ultimate 102. When driving a Carrera in Germany you need not purchase that higher premium fuel because the engine is optimized for 93 AKI Octane--Aral's SuperPlus 98. Shell's V-Power in Germany is 100 RON Octane--well above the requirement from Porsche. Canada has Ultra 94 from Petro-Canada which is 94 AKI Octane. (It is rated 101.5 RON Octane).
The bottom line is don't use an AKI Octane that exceeds 93 AKI Octane or you will be throwing away your money. The engine will be unable to exploit the excess octane potential. For those of us in California who are routinely subjected to the limited 91 AKI Octane (2 points under the engine's optimal performance rating) can add an unleaded octane booster for those occasions (racing) where you want to get the full power of which the Carrera engine is designed.
The positive side of all of this, however, is engine tune. We have benefitted immeasurably from the deletion of lead as an un-knocking compound. The engines stay cleaner inside and remain in tune much longer. The true bottom line is that maintenance is lower, over the life of the car, and that we're also not spewing a lot of crap into the environment.
In Germany, the AKI fuels (that concern us with the Carrera) include the Blei-Fri Super e.g., that from Aral which is called SuperPlus 98 and Aral Ultimate 102. When driving a Carrera in Germany you need not purchase that higher premium fuel because the engine is optimized for 93 AKI Octane--Aral's SuperPlus 98. Shell's V-Power in Germany is 100 RON Octane--well above the requirement from Porsche. Canada has Ultra 94 from Petro-Canada which is 94 AKI Octane. (It is rated 101.5 RON Octane).
The bottom line is don't use an AKI Octane that exceeds 93 AKI Octane or you will be throwing away your money. The engine will be unable to exploit the excess octane potential. For those of us in California who are routinely subjected to the limited 91 AKI Octane (2 points under the engine's optimal performance rating) can add an unleaded octane booster for those occasions (racing) where you want to get the full power of which the Carrera engine is designed.
The positive side of all of this, however, is engine tune. We have benefitted immeasurably from the deletion of lead as an un-knocking compound. The engines stay cleaner inside and remain in tune much longer. The true bottom line is that maintenance is lower, over the life of the car, and that we're also not spewing a lot of crap into the environment.
04-07-2013, 06:55 PM
#29
I live a long way from California (thankfully) and there are only a couple of stations locally that sell ethanol gas but luckily one is near the house. They sell ethanol free 93 octane at about a $0.20/gal premium over the top tier gas stations. It is worth it to me to have the ethanol free gas, to others it isn't. The Govt should get out of the business and let the consumer decide what he wants.
04-07-2013, 10:16 PM
#30
Instructor
Those of you in Louisiana appear to be in luck though.