Author Topic: Choices - Octane vs Ethanol  (Read 2192 times)

ChrisInNashville

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Choices - Octane vs Ethanol
« on: July 25, 2020, 18:16:03 »
I found a gas station near my house on the west side of Nashville that sold ethanol free 90 octane. 

I know we are supposed to use premium 93 octane

Is it worth the trade off to use ethanol free gas?
‘69 280 SL
‘24 GLE450e
Tennessee, USA

BaronYoungman

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Re: Choices - Octane vs Ethanol
« Reply #1 on: July 25, 2020, 21:31:05 »
I would make that trade if it was available to me. Just my two cents Bob
Bob "Baron" Youngman
1971 280 SL silver  1 car 0 boxes
1983 500sec Wheeler Dealer AMG w AMG coupe
1965 220se coupe restomod
1988 560sec  Japan "Yakuza Car"

badali

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Re: Choices - Octane vs Ethanol
« Reply #2 on: July 26, 2020, 16:13:52 »
I have been using the 90 non ethanol gas for several years and my car runs much better.  It starts easier and doesn't seem to have a lack of power.
Brad

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MikeSimon

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Re: Choices - Octane vs Ethanol
« Reply #3 on: July 26, 2020, 17:49:47 »
I think what you are looking at is the choice of additive. Do you want a gasoline stabilizer that neutralizes ethanol, like "Startron" or do you want an octane booster.
The non-ethanol gasoline we have in our area is premium.
Also, be aware of the fact that the octane numbers associated with the Pagoda is based on a different octane rating than the one that is available at the pump.
1970/71 280SL Automatic
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ChrisInNashville

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Re: Choices - Octane vs Ethanol
« Reply #4 on: July 27, 2020, 07:05:57 »
My recollection is that the current octane formula is different than when the car went in to service and that the current 93 is the equivalent of 98 as originally recommended by Mercedes?
‘69 280 SL
‘24 GLE450e
Tennessee, USA

MikeSimon

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Re: Choices - Octane vs Ethanol
« Reply #5 on: July 27, 2020, 14:21:29 »
The Octane rating at the pump is commonly shown (and identified) as (R+M)/2. R=Research Octane, M=Motor Octane. Because of this, it is usually 4-6 Octane points lower than in the rest of the world for the same fuel. If you are pumping 90 (R+M)/2, you are getting what MB would have called 94-96 octane in the 70s
1970/71 280SL Automatic
Sandy Beige
Parchment Leather
Power Steering
Automatic
Hardtop
Heated Tinted Rear Window
German specs
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zak

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Re: Choices - Octane vs Ethanol
« Reply #6 on: August 15, 2020, 22:21:37 »
Does everyone agree that the non- ethanol , 90 octane gas is better for our cars ?

jz   
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MikeSimon

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Re: Choices - Octane vs Ethanol
« Reply #7 on: August 16, 2020, 11:40:19 »
I would.
Just because there is more than octane to ethanol vs non-ethanol gas. I don't think we really know what kind of damage ethanol does on the long run to components in the fuel conveying system. I had some weird failures in both cars and motorcycles which can be blamed on continuous ethanol gas usage.
1970/71 280SL Automatic
Sandy Beige
Parchment Leather
Power Steering
Automatic
Hardtop
Heated Tinted Rear Window
German specs
3rd owner