Best pump gas brand
Aug 26, 2009, 03:06 AM
#76
I can also confirm that this new Shell gas SUCKS! I just filled up with Shell 93 octane, continued my drive home for about 10 minutes to make sure the gas mixes with the 2 gallons I had in the tank, and then logged a fourth gear pull. I went from my random 1 or 2 counts of knock up to 9 counts above 6200rpm. And the latest log I did was last night with almost no change in my tune. (all I had done was lower my intake cam advance a tad around redline) So, I will confirm that shell 93 octane sucks big donkey dick. I'll make sure to leave the tune as is and fill up with Sunoco 93 next and see what happens.
Aug 26, 2009, 03:43 AM
#77
I can also confirm that this new Shell gas SUCKS! I just filled up with Shell 93 octane, continued my drive home for about 10 minutes to make sure the gas mixes with the 2 gallons I had in the tank, and then logged a fourth gear pull. I went from my random 1 or 2 counts of knock up to 9 counts above 6200rpm. And the latest log I did was last night with almost no change in my tune. (all I had done was lower my intake cam advance a tad around redline) So, I will confirm that shell 93 octane sucks big donkey dick. I'll make sure to leave the tune as is and fill up with Sunoco 93 next and see what happens.
Also, the car now seems to be a little more backfire prone especially while rev matching. It only used to do it occasionally. On the ride home it did it every time I blipped the throttle. Also, nearly the split second I let off the throttle during my logged run, my SES light came on. I'm gonna get it checked out tomorrow. I have a feeling its for my rear o2 which miraculously went away on its own.
Aug 26, 2009, 04:28 AM
#78
So judging by the amount of people having issues with Shell, is it safe to say yet that whatever they did recently really messed with the knock threshold of their gas? Some posters earlier on in this thread were saying that nitrogen cannot affect the performance of their gas. How do you explain this?
Aug 26, 2009, 06:59 AM
#81
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I work for a refining company and am an operator of the processes that distilles oil into gasoline. Generally most gasolines in an area are made by the same plant or refinery. (Whatever refinery is closest). Just cause it has a brand name on it doesn't mean that brand made the gas. At the terminal for the finished product the refiner adds the brands proprietary additive (like Chevron's Techron). That is when it becomes the "branded" gasoline. Most of these additives are simple detergents to make the gas burn cleaner and prevent carbon (soot) deposits etc to form on engine parts. These additives aren't really all that different from each other either.
Difference comes in at the tank farm where the different gasoline components are blended together to make the quality of fuel that blend is for. Sometimes it is done well other times, not so well. However, since all the stations in one area are generally getting there stock from the same supplier or refiner, the gas at all their stations is the same, except for the brand additive.
Obviously, a higher octane (93 vs. 91). is better. But, the Shell station 93 is the same gas as the Chevron station 93, except for shells nitrogen based additive, versus Chevron's Techron (detergent based).
Difference comes in at the tank farm where the different gasoline components are blended together to make the quality of fuel that blend is for. Sometimes it is done well other times, not so well. However, since all the stations in one area are generally getting there stock from the same supplier or refiner, the gas at all their stations is the same, except for the brand additive.
Obviously, a higher octane (93 vs. 91). is better. But, the Shell station 93 is the same gas as the Chevron station 93, except for shells nitrogen based additive, versus Chevron's Techron (detergent based).
Now this year, Noize and I were on the same dyno the same day, both of us had filled up with shell, him in TN, me in GA. We were both throwing a lot of knock sum. It's worth mentioning that the same tune I was running that day had never thrown more than a 1 count on the dyno.
To sum it up Shell has gone down hill since the switch to the nitrogen crap. BP still seems to be good in ATL.
Aug 26, 2009, 10:46 AM
#82
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I can also confirm that this new Shell gas SUCKS! I just filled up with Shell 93 octane, continued my drive home for about 10 minutes to make sure the gas mixes with the 2 gallons I had in the tank, and then logged a fourth gear pull. I went from my random 1 or 2 counts of knock up to 9 counts above 6200rpm. And the latest log I did was last night with almost no change in my tune. (all I had done was lower my intake cam advance a tad around redline) So, I will confirm that shell 93 octane sucks big donkey dick. I'll make sure to leave the tune as is and fill up with Sunoco 93 next and see what happens.
Aug 26, 2009, 11:09 AM
#83
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I work for a refining company and am an operator of the processes that distilles oil into gasoline. Generally most gasolines in an area are made by the same plant or refinery. (Whatever refinery is closest). Just cause it has a brand name on it doesn't mean that brand made the gas. At the terminal for the finished product the refiner adds the brands proprietary additive (like Chevron's Techron). That is when it becomes the "branded" gasoline. Most of these additives are simple detergents to make the gas burn cleaner and prevent carbon (soot) deposits etc to form on engine parts. These additives aren't really all that different from each other either.
Difference comes in at the tank farm where the different gasoline components are blended together to make the quality of fuel that blend is for. Sometimes it is done well other times, not so well. However, since all the stations in one area are generally getting there stock from the same supplier or refiner, the gas at all their stations is the same, except for the brand additive.
Obviously, a higher octane (93 vs. 91). is better. But, the Shell station 93 is the same gas as the Chevron station 93, except for shells nitrogen based additive, versus Chevron's Techron (detergent based).
Difference comes in at the tank farm where the different gasoline components are blended together to make the quality of fuel that blend is for. Sometimes it is done well other times, not so well. However, since all the stations in one area are generally getting there stock from the same supplier or refiner, the gas at all their stations is the same, except for the brand additive.
Obviously, a higher octane (93 vs. 91). is better. But, the Shell station 93 is the same gas as the Chevron station 93, except for shells nitrogen based additive, versus Chevron's Techron (detergent based).
+1. All gas in a given area comes from the same source. They also make the mid grade by mixing the top grade and lower grade 50/50, from what I understand.
Theres a really interesting book on the industry, oil on the brain I think it was called. The writer goes through the entire oil supply chain. She goes to a refinery to see how they work then rides on the trucks that haul the oil, talks to company owners etc.
Its really entertaining and informative. The author mentions that all the gas comes from a refinery for a given area and the detergent package is the difference. How razor thin gasoline margins are (that 3.00 and 9/10 of a cent) for gas stations. How the little flammable symbol on the truck hauling the has a number and that number tells firefighters what kind of fuel in on board. How the trucks cannot go faster than the speed limit which is constantly being recorded.
A lot of it is really surprising and departs quite far from what is popularly believed.
Aug 26, 2009, 11:38 AM
#84
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I mainly use Shell and will make a drive for it; then in emergency ill use Sunoco then BP and nothing else; I only reason a said BP cause it burn clean and doesn't have a strong smell like the others BUT that CRAP goes quick; if i put in a tank of shell, it will last 5 to 6 days before the light comes on but BP in 3 to 4 days. Seems to me that shell and sunoco burns slower and is heavier.
93+ octane only
93+ octane only
Sep 1, 2009, 03:55 AM
#87
Just to bring this thread back up.
I filled up with Sunoco Ultra 93 on the way in to work today (had about a quarter tank of the crap Shell left over) and logged a few pulls on the way home. Not only did my car overboost and hit about 295 load (highest load value i've recorded on my car), but the motor did not knock once. Not even a blip of one or two. I was shocked. I hit a max boost of 28.5psi and the car did not knock once. I logged three pulls to verify what was going on... two short third gear blasts and a full third gear and half of fourth gear pull and still nothing.
So with 10 degrees cooler weather, 1.5psi of more boost, and Sunoco Ultra 93 Octane, I completed eliminated the 9 counts of knock I had prior with the Shell gas. And just for anyone who is really paying attention, the tune in the ecu now has more ignition timing in it above 6000rpm than before.
I filled up with Sunoco Ultra 93 on the way in to work today (had about a quarter tank of the crap Shell left over) and logged a few pulls on the way home. Not only did my car overboost and hit about 295 load (highest load value i've recorded on my car), but the motor did not knock once. Not even a blip of one or two. I was shocked. I hit a max boost of 28.5psi and the car did not knock once. I logged three pulls to verify what was going on... two short third gear blasts and a full third gear and half of fourth gear pull and still nothing.
So with 10 degrees cooler weather, 1.5psi of more boost, and Sunoco Ultra 93 Octane, I completed eliminated the 9 counts of knock I had prior with the Shell gas. And just for anyone who is really paying attention, the tune in the ecu now has more ignition timing in it above 6000rpm than before.
Sep 1, 2009, 06:53 AM
#88
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I noticed a difference recently from spring-time Shell gas to summer gas. In early June, I had no issues at 7000-7500 pulling hard in 4th gear. The past weekend, on gas from the same outlet, the X starting missing pretty noticably at that point. Missouri/Gateway clean air region is screwed.... while we're allowed to get 93 Octane (unlike CA), our emission additive requirements to reduce CO and NO2 are close to the same. Net, gasoline here sux all around. I'll have to start budgeting time to travel to the country before tracking....
