90 octane, ethanol free
03-23-2019, 01:07 PM
#1
Drifting
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90 octane, ethanol free
So I'm in a bit of dilemma. There are a few ethanol free gas stations around me but it seems the highest octane that any of them has is 90. What says the group about using this in my '78?
03-23-2019, 01:24 PM
#2
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I found a station near me and tried out a tank. I added octane boost to get to 91. Noticed absolutely no difference, except the engine seemed to idle a bit rougher with the ethanol free. I am no fuel expert but I just tried it out because it was available, purely unscientific. Interested then hear what other who know more about this have to say.
By the way, the gas I used was 88 octane. I'm in Colorado.
By the way, the gas I used was 88 octane. I'm in Colorado.
03-23-2019, 01:57 PM
#3
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Your car was meant to run on regular gas - RTFM 8>)
IIRC all 4.5L CIS & LJet cars run on Regular here in the States so the use of Premium is a waste.
IIRC all 4.5L CIS & LJet cars run on Regular here in the States so the use of Premium is a waste.
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
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928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
03-23-2019, 02:16 PM
#4
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03-23-2019, 03:18 PM
#5
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Good, I'll save myself money then and run 87. For some reason I always assumed 91 was recommended, I thought I read it in the manual.
03-23-2019, 03:36 PM
#6
Drifting
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03-23-2019, 03:38 PM
#7
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03-23-2019, 03:49 PM
#8
Burning Brakes
OK, I have a GT which requires higher test gas, but here are some other considerations, why you might want to use ethanol free gas:
1.) Ethanol might not be compatible with older fuel systems
2.) I **thought** ethanol pulls more water from the environment, which is a problem if the car is stored for longer periods
I have GB's fuel lines and blue hose for the intake pump, so probably 1.) does not even have an impact on me now. Nonetheless, that's why I am still using ethanol free gas.
1.) Ethanol might not be compatible with older fuel systems
2.) I **thought** ethanol pulls more water from the environment, which is a problem if the car is stored for longer periods
I have GB's fuel lines and blue hose for the intake pump, so probably 1.) does not even have an impact on me now. Nonetheless, that's why I am still using ethanol free gas.
03-23-2019, 06:10 PM
#9
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It says in the owners manual for my 81 that the car was designed to run on up to 10% ethanol fuels and if there is an issue to revert to ethanol free.
It wont hurt anything. Just run the octane rating your owners manual states the car requires. My 89 needs 91 and my 81 needed 87.
It wont hurt anything. Just run the octane rating your owners manual states the car requires. My 89 needs 91 and my 81 needed 87.
03-23-2019, 06:54 PM
#10
Drifting
Thread Starter
03-24-2019, 12:52 AM
#11
Rennlist Member
Yep to all of the above. I run e-free regular in Blumaxx. Have for years, and certainly store it that way over the winter. Nice having a low compression engine.
03-24-2019, 12:58 AM
#12
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"I added octane boost to get to 91"
You got it to 90.1, actually.
The boosters are a scam.
Now, go buy yourself gallons of Xylene..maybe.
Dont get so worked up over Ethanol, Knock will hurt you more, faster.
You got it to 90.1, actually.
The boosters are a scam.
Now, go buy yourself gallons of Xylene..maybe.
Dont get so worked up over Ethanol, Knock will hurt you more, faster.
03-24-2019, 01:42 PM
#13
RL Community Team
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Anyone looking at this thread for reference that has forced induction is better off with 93 octane that has up to 10% ethanol than ethanol free 90 octane to prevent engine knock / detonation under boost.
03-24-2019, 03:48 PM
#14
Porsche state 10% is unsuitable
https://www.porsche.com/uk/aboutporsche/pressreleases/pcgb/?lang=none&pool=uk&id=2011-05-23-classic
Here in the UK we only have the option of 5% or 10%. I wonder if ethanol free was available if they would recommend that.
https://www.porsche.com/uk/aboutporsche/pressreleases/pcgb/?lang=none&pool=uk&id=2011-05-23-classic
Here in the UK we only have the option of 5% or 10%. I wonder if ethanol free was available if they would recommend that.
03-24-2019, 03:53 PM
#15
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Porsche state 10% is unsuitable
https://www.porsche.com/uk/aboutpors...-05-23-classic
Here in the UK we only have the option of 5% or 10%. I wonder if ethanol free was available if they would recommend that.
https://www.porsche.com/uk/aboutpors...-05-23-classic
Here in the UK we only have the option of 5% or 10%. I wonder if ethanol free was available if they would recommend that.
Pick your level of discomfort...given that you can buy new lines with modern material.