90 Octane or 93
Le Mans Master
Joined: Oct 2005
Posts: 5,040
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From: Tampa Florida
Sr.Random input generator
Joined: Jan 2008
Posts: 7,777
Likes: 2,210
From: Sammamish, WA
What matters is the octane rating and the detergents inside. Ethanol is not a bad thing at all. It has a bit less energy density, so fuel with ethanol causes a bit more fuel consumption, but that's it. 10% is not enough to cause any corrosive issues, either.
We only have 92 octane in WA, and my local track sells no ethanol 92 octane. I still always prefer the 10% ethanol mixed fuel and bring my own, since the engine learns and optimizes for the fuel type, and there's no reason to upset it.
In my area, the highest octane fuels are from 76 and Chevron, and I get my fuel from them only. Shell has good detergents, but its octane is a bit less than the others (something I've learned the hard way when I used to tinker with turbo engines).
We only have 92 octane in WA, and my local track sells no ethanol 92 octane. I still always prefer the 10% ethanol mixed fuel and bring my own, since the engine learns and optimizes for the fuel type, and there's no reason to upset it.
In my area, the highest octane fuels are from 76 and Chevron, and I get my fuel from them only. Shell has good detergents, but its octane is a bit less than the others (something I've learned the hard way when I used to tinker with turbo engines).
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Joined: Sep 2019
Posts: 93
Likes: 36
From: Tampa, FL
From what I have read it appears that while the cheaper gas may have the same octane rating and may perform the same, the top tier gas companies have a far better additive package for cleaner combustion etc. I only run top tier fuels for this reason.
Again, just what my research has shown.
Again, just what my research has shown.
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Le Mans Master
Joined: Jul 2000
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From: North Dallas 40 TX
The car's fuel system and ECU was designed to accommodate E10. 93 Octane will be better.
If it were car from 60's with no fuel system updates, 90 Octane and back down timing. The ethanol would act as a solvent on certain fuel system components, that were not designed to resist ethanol.
If it were car from 60's with no fuel system updates, 90 Octane and back down timing. The ethanol would act as a solvent on certain fuel system components, that were not designed to resist ethanol.
