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

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Dave Finburgh
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Re: How does ethanol in gas affect 356 engine/fuel system?

#91 Post by Dave Finburgh »

I have had a lot of problems due to Ethanol...several rebuilds of the carbs, eventually a new gas tank and consistent fuel evaporation problems, ( and I run her at least once a month). Here's the odd thing, my neighbor has a '67 Vette with fuel injection, runs the car maybe once every two years...and it starts up like a brand new car!! No issues whatsoever, and he doesn't even use Stabil!! Crazy how the fuel injection and better sealing seems to be the trick....regardless of the ethanol!!


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Graeme Langford
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Re: How does ethanol in gas affect 356 engine/fuel system?

#92 Post by Graeme Langford »

I found out yesterday that Esso Supreme unleaded has a zero ethanol content. I will be switching to using this in future. A nuisance as I have a full tank of Shell Vpower which has a 5% ethanol content
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Re: How does ethanol in gas affect 356 engine/fuel system?

#93 Post by Martin Benade »

An excellent excuse to drive your car!
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Eric McKinley
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Re: How does ethanol in gas affect 356 engine/fuel system?

#94 Post by Eric McKinley »

David I enjoyed reading that article, very informative, especially the part with regards to the lead levels within criminals and the reduction in crime years later after the removal of lead from fuel.

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Graeme Langford
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Re: How does ethanol in gas affect 356 engine/fuel system?

#95 Post by Graeme Langford »

Graeme Langford wrote: Wed Jul 22, 2020 3:26 am I found out yesterday that Esso Supreme unleaded has a zero ethanol content. I will be switching to using this in future. A nuisance as I have a full tank of Shell Vpower which has a 5% ethanol content
My local Esso garage is not ethanol free. States 5% on the pump. Might have to hunt around
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Brian R Adams
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Re: How does ethanol in gas affect 356 engine/fuel system?

#96 Post by Brian R Adams »

I've been addressing Zenith, throttle linkage, and distributor issues, and have settled for now on my spare 050 distributor. With rebuilt Zeniths and well-synced linkage, my stock 'A' Super runs better than it ever has for me, on ethanol-free gas. So, having been keeping my fuel tank near empty, adding a gallon as required (the tank filler leaks and I plan to replace the tank soon) I decided to burn off the ethanol-free and test the current setup with our summer blend which "may contain up to 10% ethanol". The difference is significant. I had the 050 timed to idle at ~6 BTDC @~875 rpm, and it was rock solid there, and reached ~35 BTDC at 3000 rpm with very slight timing jitter. I had adjusted the idle mixture screws to the rich side of the max rpm range.

Running the ethanol blend, the idle speed remained ~875, but it "hunts" a bit, wandering up to 900+ for periods, then back down. (Note: I did not touch the idle mixture screws. I suspect it's idling leaner now with the oxygenated blend, but as I noted the base rpm did not change.) On the road, I took it up my usual test hill and noticed it feels a little mushy when I open it up, and while it does not stumble it doesn't react quite as instantly to stomping WOT from a ~2500-3000 rpm uphill cruise in 2nd or 3rd gear. Once at WOT it doesn't climb the hill quite as willingly, I can definitely sense a loss of power. However it's still basically running ok, no lean condition popping coasting downhill, so I don't think the idle mixtures are too lean.

PS Ethanol-free generic (not racing) gas only just became available here in the past couple of years, and only at Maverik stations. It's typically priced about 40 cents higher than regular ethanol.

PPS The engine takes a lot longer to warm up as well. Until it does it runs fairly crummy. On pure gasoline it runs well after a minute of warm-up.

Brian
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Tim Dawson
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Re: How does ethanol in gas affect 356 engine/fuel system?

#97 Post by Tim Dawson »

Graeme Langford wrote: ↑
Wed Jul 22, 2020 3:26 am
I found out yesterday that Esso Supreme unleaded has a zero ethanol content. I will be switching to using this in future. A nuisance as I have a full tank of Shell Vpower which has a 5% ethanol content

My local Esso garage is not ethanol free. States 5% on the pump. Might have to hunt around
1958 356A
It's only the Esso Synergy 99 fuel which is ethanol free in the UK, even though it states E5 on the pump. That's because there is no E0 rating! Problem is the number of their stations that have this fuel are few and far between. In London there is only one in Wembley, so not much use if you live miles away!!! I think we need to get used to ethanol being a fact of life, and it will increase to 10% in most fuels as of 2121.

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

#98 Post by David Jones »

Try increasing the idle jet size by 5 points and see if that makes a difference. As you say it is now running leaner than before. Most street engines are tolerant of small mixture changes or you would not be able to drive over mountain passes but in the 50's and 60's nobody was anticipating E10.
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Martin Benade
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Re: How does ethanol in gas affect 356 engine/fuel system?

#99 Post by Martin Benade »

It’s so nice we have a fuel expert onboard. Thanks, David.
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Re: How does ethanol in gas affect 356 engine/fuel system?

#100 Post by David Jones »

Martin, all it takes to be an expert is to know 1% more than the next person and have a foreign accent. I qualify on both. My wife is the only one close by and she knows Arabian horses well but nothing about gasoline.
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Martin Benade
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Re: How does ethanol in gas affect 356 engine/fuel system?

#101 Post by Martin Benade »

I think your percentage is much higher than 1%. As your accent gets assimilated does it make you know less?
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Re: How does ethanol in gas affect 356 engine/fuel system?

#102 Post by jay abrams »

The first 15 or so years I owned my car, not once did I replace the O-ring in the Zenith jet cover. Since the introduction of ethanol, I now keep a stash of them on hand. Seems they only last a couple years before they begin to disintegrate and leak.
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John Clarke
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New Gas here in the UK from Today

#103 Post by John Clarke »

I know there is a sticky on this. But
went to top up with gas and noticed that the new E10 fuel is all we can buy. from Today at most pumps. Diesel and Unleaded E10 92 RON I think.
The 356 didn't seem to have it's usual punch. Probably imagination. I just know that I can normally feel 'seat of the pants' performance changes from the tiniest adjustments in timing or mixture settings. Its not good !
David??
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Re: New Gas here in the UK from Today

#104 Post by David Jones »

I did read that world wide the sale of unleaded gas has stopped for road use but there was no reason that I know of to stop the sale of 93 AKI gas (petrol) I will see what I can find out. There are a lot of modern cars that require 93 octane AKI minimum. Looks like the UK rating is by RON or (ROZ) and 97 octane is still available.

During summer 2021, the standard (95 octane) petrol grade in Great Britain will become E10. In Northern Ireland, this will happen in early 2022. The change in fuel applies to petrol only. Diesel fuel will not be changing.

https://www.gov.uk/guidance/e10-petrol-explained
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Re: New Gas here in the UK from Today

#105 Post by Hugo Sheers »

Jay, premium petrol remains formulated as 5% ethanol. Look out for Esso Supreme:

'Although our pumps have E5 labels on them, our Synergy Supreme+ 99 is actually ethanol free (except, due to technical supply reasons, in Devon, Cornwall, North Wales, North England and Scotland). Legislation requires us to place these E5 labels on pumps that dispense unleaded petrol with ‘up to 5% ethanol’, including those that contain no ethanol, which is why we display them on our Synergy Supreme+ 99 pumps.'

https://www.esso.co.uk/en-gb/fuels/petrol

KTF
Hugo

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