How does ethanol in gas affect 356 engine/fuel system?

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Brian R Adams
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Re: How does ethanol in gas affect 356 engine/fuel system?

#151 Post by Brian R Adams »

I'll say again: if ethanol-free gas is available, use it! Out west the expanding Maverik chain carries it. It's "regular" octane yet more expensive, but you'll love how it runs, and the discussed fuel system problems are banished. If your state or county forbid it, that's regrettable.
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Paul Lima
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Re: How does ethanol in gas affect 356 engine/fuel system?

#152 Post by Paul Lima »

Just a reminder; this is a product that works in our cars and is safe with modern fuels. https://www.gates.com/us/en/search.p.42 ... 00001.html

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Martin Benade
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Re: How does ethanol in gas affect 356 engine/fuel system?

#153 Post by Martin Benade »

Their description is confusing. It says 100% methanol only, blends are not acceptable.
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Paul Lima
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Re: How does ethanol in gas affect 356 engine/fuel system?

#154 Post by Paul Lima »

I think you mis-read it: "Gasoline, Gasoline/Ethanol (E10, E15, E85), 100% Methanol only (Methanol blends not recommended). Diesel, Diesel/Bio–Diesel blends, 100% Bio–Diesel (SME, RME, and PME Bio–Diesels are acceptable"

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Brian R Adams
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Re: How does ethanol in gas affect 356 engine/fuel system?

#155 Post by Brian R Adams »

Martin Benade wrote: Tue Feb 28, 2023 10:49 am Their description is confusing. It says 100% methanol only, blends are not acceptable.
While I admit the description is a bit ambiguous semantically WRT "100% methanol", these word are all you need to take to heart:

Gasoline, Gasoline/Ethanol (E10, E15, E85)

That covers everything that comes out of a ubiquitous automotive filing station pump (with the possible exception of some sort of "racing fuel".) If those blends are stated as safe in the hose product, there's and end of it. (As an aside, 100% methanol is also listed as safe, but not a blend of methanol and other non-gasoline additives.)
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Randy Mittelstet
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Re: How does ethanol in gas affect 356 engine/fuel system?

#156 Post by Randy Mittelstet »

Reading this thread brings up several things I would like to ask the group’s opinion regarding the which gasoline to use.
My 1960 early T5, which I’ve owned since 1978, has the same engine which I’ve never opened fortunately.
I think it had 1720 upgrade early in its life based on several clues.

The fan shroud had an old “label” on it saying Isky Cam and the intake & exhaust specs were noted. No ID on which Isky was used. This info was lost many years ago.
The rear had also been lowered.

I don’t do any racing but really enjoy the club drives on our curvy roads locally. We live in the Denver area so driving at altitude may factor into this.

I now have access to ethanol free gas with 87 octane.
I normally use the 91 octane with the usual 10% ethanol.

So my question is:
if I use the 87 octane with the advantages of being ethanol free, will the lower octane be detrimental to the engine?

Also, are there any factory specs regarding minimum octane ratings for the 356 normal and Super 90 if different?

Thank you.
Randy Mittelstet
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Brian R Adams
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Re: How does ethanol in gas affect 356 engine/fuel system?

#157 Post by Brian R Adams »

Randy Mittelstet wrote: Fri Aug 18, 2023 2:01 pm ...
I think it had 1720 upgrade early in its life based on several clues.

The fan shroud had an old “label” on it saying Isky Cam and the intake & exhaust specs were noted. No ID on which Isky was used. This info was lost many years ago.
...
if I use the 87 octane with the advantages of being ethanol free, will the lower octane be detrimental to the engine?
That depends largely on the compression ratio, which (as modified) you're presumably not privy to. But the experts will correct me if I oversimplify. ;-)
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Re: How does ethanol in gas affect 356 engine/fuel system?

#158 Post by David Jones »

87 octane will be more than adequate in Denver. Octane requirement reduces with increasing altitude. I run 87 at 1000 ft ASL. That with 1720 and 9 to 1 CR. You probably cannot even buy 93 Octane in Denver. I also run 10% ethanol with no apparent ill effects for the last 30 years.
If I had known I would live this long I would have pushed the envelope a little harder.
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Randy Mittelstet
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Re: How does ethanol in gas affect 356 engine/fuel system?

#159 Post by Randy Mittelstet »

so corn free 87 it is then. My fuel pump diaphragm and fuel hoses should like it better too.
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Brian R Adams
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Re: How does ethanol in gas affect 356 engine/fuel system?

#160 Post by Brian R Adams »

Randy Mittelstet wrote: Fri Aug 18, 2023 8:51 pm so corn free 87 it is then. My fuel pump diaphragm and fuel hoses should like it better too.
Your foot will like it even better for sure, the energy density of gasoline being much higher than that of ethanol. I find my Zeniths at a mile above sea level and above are easier to tune for smooth, snappy acceleration.
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Alan Klingen 2
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Re: How does ethanol in gas affect 356 engine/fuel system?

#161 Post by Alan Klingen 2 »

Doesnoteffectthe rnning too much but will over time degrade all the rubber parts it comes in contact with. Alan The Stable.

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Martin Benade
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Re: How does ethanol in gas affect 356 engine/fuel system?

#162 Post by Martin Benade »

Brian, in what way do the Zeniths get easier to tune at higher altitude? And that’s in spite of about a 15% power loss at 5000 feet?
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Re: How does ethanol in gas affect 356 engine/fuel system?

#163 Post by Eric McKinley »

I watched this today, an interesting concept in relation to removing the ethanol from the fuel.

https://www.youtube.com/watch?v=onCG7mIprfE

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Brian R Adams
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Re: How does ethanol in gas affect 356 engine/fuel system?

#164 Post by Brian R Adams »

Martin Benade wrote: Sat Sep 16, 2023 5:38 pm Brian, in what way do the Zeniths get easier to tune at higher altitude? And that’s in spite of about a 15% power loss at 5000 feet?
I did indeed mention that I live at altitude, but that wasn't the operative part of the statement, just a FWIW. I do live at higher altitude, and the car does dial in and run better on ethanol-free gas for whatever reason. Of course undiluted gasoline w/ its higher energy density I would think somewhat offsets any power loss at altitude.
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Alan Klingen 2
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Re: How does ethanol in gas affect 356 engine/fuel system?

#165 Post by Alan Klingen 2 »

What it affects most would be the life of the Parts made of rubber And also being hydro scopic it holds water and can rust things that come in contact with the fuel. There are fuell additives that help remove water from the fuel system. Alan The Stable.

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