Got to thinking the other day, what would it take to run E85 instead of normal gas in an older car such as our 914s?

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There is the possibilty that you would need to change all of the rubber out to a more more modern fuel resistant rubber, convert your hardlines to stainless and pick up a different fuel pump. You will also need to retune the engine to take advantage of the fuels different characteristics. The fuel is not as efficent as regular gasoline so you will end up using 20-30% more per fill up than you will of regular gas. Make sure you can get it really cheap to offset the drawbacks.

Not to mention a fully stainless exhaust system.

There was a thread about this not to long ago, had alot of good info. You might want to do a search.

E85 requires an afr of about 9.7:1 (versus 14.5:1). This gives you an idea of what needs to change; induction, injection, cam, exhaust... basically everything.

I'll be developing an engine over the next year as a research project through the university that will explore E85 in race motors. Hopefully in a few months from now I'll be able to give a more educated answer. If its a good solution for fuel, I see no reason why it wouldnt be a good conversion in a 914 (or any car). It is tough to obtain, though, in most of the US.

I did. I searched for "E85" and came up completely empty. Maybe I should just give up on the forum's search box and use a constrained Google search in the future...

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Why do you think you would need a stainless steel exhaust? EGTs will be lower with ethanol.

Ethanol that is premixed in the pump may be different but if you mix it with regular gas it will give an octane level of 105. Would be nice to see how that changes when it comes to the mass market.

all alcohol fuels are highly corrosive, to rubbers and plastics. alcohol is prone to water absorption and that is crossive to metals.

I am well aware of the effects of ethanol on plastics and rubber. It will not however have any effect on the exhaust system.

I found something out the other day about the water thing. When you mix ethanol (pure) and gasoline to get E85 if there is any more than .010 percent water in the alcohol then the gas will not mix with it. It will cause the gas to float on the surface of the ethanol.

So I am not so sure about how this effects ethanol after it is mixed.

I don't know if the D-jet components will tolerate the fuel. I do know the D-jet injectors are quite oversized for the application - so the addition of a megasquirt with the stock injectors, assuming they don't come apart *MIGHT* be able to get appropriate ratios.

The new MS stuff also supports the FlexFuel sensors which can tell on the fly what the ratio of alcohol to gasolene is.

105 octanes? Does that mean we can increase our compresion ratios?


Completion make me happy.

Depends on how it is mixed in the future.

I checked the info and I found RON of 112-120. Crank up the compression and boost.