Is Ethanol Free Preferred Gas To Use In 911 SC

[911Bound]

I am soon to be getting my first ever Porsche on the road and was wondering what type of gas I should be using. There a a few ethanol-free gas stations close-by and I was wondering what gas is best for a 1980 911 SC. My shop suggests at least 91 octane and add an additive to lessen the effects of the ethanol but if I can get the ethanol free is that the way to go?

Thanks in advance for any help...

[DRACO A5OG]

Ag Plus - COUNTRYMARK
1105 Production Rd, Fort Wayne IN
260-471-4017
Ethanol-free octane ratings: 91

for others lucky not to be SoCal: you can find your E free gas here: Ethanol-free gas stations in the U.S. and Canada

Yes, your car will be much happier

[Steve@Rennsport]

CIS-equipped cars should get ethanol-free gasoline, but not at the cost of octane. 91 or better without ethanol would be just fine.

[Quicksilver]

In pretty much ANY car it is better to get ethanol free gas.
The only exception would be "flex fuel" designed cars but that is a whole other kettle of fish.

[VFR750]

Read your owners manual. 911sc is designed for e10.

[Steve@Rennsport]

Originally Posted by Quicksilver

In pretty much ANY car it is better to get ethanol free gas.
The only exception would be "flex fuel" designed cars but that is a whole other kettle of fish.

Well sir,...not necessarily.

CIS cars are THE most intolerant of water so thats why ethanol fuels should be avoided. EFI systems are not as fussy, especially when measures are taken to avoid problems.

Turbocharged engines can benefit from ethanol due to its 112 RON octane rating, provided AFR values are set up properly.

Naturally, all of the elastomers in the fuel system must be compatible.

[Jdub]

I'd only add that if you know the car will be idle for some time (Winter?) you do want Ethanol-free gas, mixed with a good stabilizer, up to Full (that's what I do anyways).

[MBAtarga]

Originally Posted by VFR750

Read your owners manual. 911sc is designed for e10.

Never heard or read this. How sure are you?

[allaircooled]

I have an app on my iPhone called Pure Gas that tells me all the ethanol free gas stations that are nearby. It will come in handy for when I drive my 911 again.

[Charles Freeborn]

and a little of this never hurt.... http://www.amazon.com/Torco-Accelerator-32oz-Best-Additive/dp/B004ZO3VN0/ref=sr_1_7?s=automotive&ie=UTF8&qid=1455849854&sr=1-7&keywords=octane+booster

[tirwin]

Originally Posted by Steve@Rennsport

Well sir,...not necessarily.

CIS cars are THE most intolerant of water so thats why ethanol fuels should be avoided. EFI systems are not as fussy, especially when measures are taken to avoid problems.

Turbocharged engines can benefit from ethanol due to its 112 RON octane rating, provided AFR values are set up properly.

Naturally, all of the elastomers in the fuel system must be compatible.

Steve, would putting a bottle of Heet in once in a while be a good idea on a CIS car?

[tcar]

Originally Posted by VFR750

Read your owners manual. 911sc is designed for e10.

Don't think that is true... no mention in SC Owner's Manual.

(I have my SC Owner's manual in front of me as I post.)

[manbridge 74]

With all due respect to Sir Steve, it does depend on temp somewhat. I recently fired up a 7 year garage stored E10 fueled car with no issue.

Fort Lame Indiana and a car parked outside summer and winter? All bets off.

[VMAX1]

Always wondered why my 87 Carrera would run better when there was 1/4 tank left. My assumption was I have burnt all the E10 93 crap out and EO 90 was at the bottom of the tank, after separation. So , I just started using EO 90 and car runs and idles like never before. Took several tanks, and started running better and better. I have found EO 110 @ $2.59 a gallon and was wondering if I could run the 110 without issues? Just wanted to add... All the backfire thru exhaust has stopped, too. Every now and then I get a small pop, but not like before.

[universeman]

I have seen the reference to e10 in my SC owners manual for sure. I was surprised by it. It's there, when I'm near the book I'll post a picture.

[DRACO A5OG]

So I guess we lost OP? Don't you just love talking to ourselves? :-)

[Spumato]

If the 911SC has CIS, then you never want to use Ethanol. Bear in mind that the last 911SC was manufactured in 1983. We've learned a good deal about fuel since then, and it's quality in general has done nothing except decline. Plus, as expensive as a CIS system is to fix/replace, I would not want to risk someone's objective opinion that they read it in their manual. Take the high road and run no ethanol fuel in your car.

[Steve@Rennsport]

Originally Posted by tirwin

Steve, would putting a bottle of Heet in once in a while be a good idea on a CIS car?

Hi Tim!

Once in a while, OK.

The key thing is to prevent water in the fuel in the first place and you do that by storing the car completely full of fuel that minimizes the air space in the tank.

Remember, ethanol is highly hygroscopic so it has an affinity for water absorbtion. Further, ethanol separates during storage and that can trigger serious corrosion issues in the tank as well as in the fuel distributor.

Using Marine Stabil goes a long way toward preventing such problems.

[universeman]

From page 24 of the SC Owner's Manual:

"Porsche vehicles are designed and certified to use gasoline as specified under "Fuel Recommendation." You may decide to use gasohol in your Porsche, provided it contains not more than 10% ethanol and the octane requirements for your car are met.

However we strongly recommend to switch back to gasoline without ethanol, if you experience the following adverse effects on your vehicle because of the use of gasohol.

- Deterioration of drivability and performance

- Substantially reduced fuel economy

- Generation of vapor lock and hot start problems, especially at high altitude or at high temperatures

- Engine malfunction or stalling.

The continued use of gasohol under these conditions may adversely affect the emission control system of your vehicle."

And in bold: "Porsche recommends not to use any fuel additivies. [sic]"

Take that for what it's worth. Of course ideally there would be no ethanol (damn politicians) in our gasoline. I live curiously in an oil-rich state but there are no eth-free stations within 80 miles of my house -- so while I would prefer to fill up on 100% gasoline, it's just not practical for me.

Note they mention potential to damage not the engine itself but the emissions control system (read: catalytic convertor) which I don't have anyway on my car regardless. With all respect to those here, if Porsche put it in their documentation for the car, they probably had confidence that it was accurate information.

Just like overall engine technology, I'm willing to bet that ethanol quality and technology has also advanced over the last 36 years. So the fuel now is likely much better than the e10 Porsche tested.

Just some food for thought. Cheers!

[tcar]

No mention of e10 in my SC Owner's Manual... and it's page 19 in my manual - 1978.

Do you have a later SC manual...???