f4 plt

On my 997 the owners manual states that up to 10% ehtanol can be used in the vehicle with no adverse affects. However my '83 SC was produced long before the crazy idea of using food to make fuel that is less clean than normal gas and produces less energy... .got that off my chest. So what is the feeling as to using up to 10 % ethanol gas in our cars since fewer and fewer station have corn free gas available.

GothingNC

Try to keep water out of your tank, change fuel filter often, search for stations without Ethanol

https://rennlist.com/forums/showthre...ferrerid=27687

Mine had vapor lock after fueling up at a BP with Ethanol, problem went away switching to Shell Premium Petrol

John

Driver8

You might want to look in to K100 fuel treatment.

http://www.k100fueltreatment.com/main.html

theiceman

Ethanol VERY BAD for CIS systems and can cause premature corrosion of said systems when water seperates from gas .. should ONLY use ethanol free gas .. which thankfully we can still get here i Canada as we like to eat our corn instead ..

GothingNC

Now the EPA is pushing for 15% Ethanol

John

rbcsaver

I'm for converting All politicians into Ethanol. However, manure composting
is probably the best option , since they are ALL FOS, and far better served for
the latter. Especially, since they are ALL pounding us all up the AH anyway.

RollingArt

I'm in CA and have been running my '73 911T on the ethanol doped gas for a couple years. No sign of any problems yet.



Phil

911Dave

I have asked the following question several times in different forums and no one has yet given me a clear answer:

Why are CIS systems more susceptible to ethanol's bad effects than any other injection system? For instance, why is 10% ethanol okay for Motronic or MFI or carbs, but not CIS? Is CIS made out of some weird alloys that aren't used in any other system?

Everyone keeps saying ethanol is bad for CIS but no one gives a definitive explanation of WHY. I even e-mailed Bruce Anderson about this and all he did was send me a link to an article on the basics of CIS, and it didn't even mention anything about fuel types or even begin to answer my question.

Who's ready to step up and explain in detail what it is about CIS that is worse than other types when it comes to ethanol?

tvanbroekhoven

Good question

+1

+ extra question

Is it possible to make a CIS 911 run on e85 and if not, can it be done with either Megasquirt or carbs AND what would be best ?

(ps: sorry I did not know the answer to your question )

theiceman

The man with the answer is Steve ... I bet he will chime in soon ...
But with more modern cars I bet we are still to see the long term efects of ethanol in gas ... ethanol and plastics do not get along so time will tell..

tvanbroekhoven

That's actually very true. I always forget to use a condom when I'm drunk


ok, back on topic

theiceman

and it will make you blind to boot .. so you think your scoring a 10 !!!

Houpty GT

Glad to see you thinking and asking questions. Panorama had an article on E10 fuel a year ago. The said that it could cause issues for the MFI, carb, and non-02 sensor CIS cars. The mentioned that the Lambda equiped cars should be OK because the O2 sensor can compensate for the difference. As for the difference: Ethanol has about 80% the energy of Gasoline. E10 replaces 10% of the gas with a fuel that has 20% less energy given a difference of about 2% leaner. The main problem they stated was that ethanol will be separated if there is any water in the tank and this can cause rust issues for cars that sit but the ones that go through tanks of fuel with use should be OK. The claim against rust and its issue with CIS is it can cause problems clogging the fuel passages inside the fuel distributor. Maybe the injectors also.

Carbs can be retuned if you know how. I ran my BMW on my blend of E60 with a little tuning of the overly rich carb just to say I did it. MFI may be the worse off.

I would like to add some additional information. Ethanol is alcohol and it is an acid. Acids react with metals so they are corrosive. Aluminum has a protective layer of metal that has reacted with oxygen on the surface and ethanol will remove this leaving the next layer of fresh aluminum to react. I don't see this reaction taking place in the CIS any faster than the same reaction that is taking place inside the combustion chamber on your car and every other car on the road. E10 is not going to be as good as regular gas. Just as unleaded was not as good as leaded was. I am not worried about E10.

Brazil has been running ethanol for a long time and I would like to see what kind of CIS injection systems they sold down because of it.

Steve Weiner-Rennsport Systems

The use of E10 is a real issue for all CIS-equipped Porsches, '73 to '83, for several reasons. Here are just a few:

1) Ethanol is hygroscopic and the absorbed moisture facilitates and accelerates fuel system corrosion of any non-stainless steel parts.

2) Ethanol attacks and dissolves elastomers in the fuel system thats not made from Viton. This means that any rubber parts: gaskets, seals, O-rings, fuel lines made from rubber will suffer.

3) Ethanol has 1/3 less BTU's per gallon and as such, requires richer fuel mixtures than gasoline. The fuel pump, injectors, and Fuel Distributor components do noit always have sufficient fuel delivery capacity (it varies by year) to maintain optimal air-fuel ratios. These engines will run leaner, all things being equal, and that makes more heat.

4) Ethanol is a powerful solvent and washes the cylinder walls of their lubrication. Ethanol dilutes regular engine oils so more frequent oil changes are recommended. Remember, OEM's are not concerned about this; the motor simply must make it through the warranty period.

5) Ethanol is very detonation resistant, however an engine using E10 really needs different ignition timing maps (advance curves) and more compression to take advantage of this fuel's characteristics. This is not easy to do for a DIY'er.

This is a very complex subject and I've just touched on the highlights. If I had time, I could write a book on this,.....

I do hope this helps,

911Dave

Steve, those are all good explanations of why ethanol in gasoline is bad for fuel systems IN GENERAL, but once again it appears to be a canned answer that doesn't address why CIS is specifically MORE VULNERABLE than other fuel delivery systems.