991.2 91 (no ethanol) vs 93 (ethanol) fuel
06-30-2018, 10:47 PM
#1
991.2 91 (no ethanol) vs 93 (ethanol) fuel
2017 (991.2 C4S)
I'm in a bit of a dilemma. I can buy 91 no ethanol citgo (top teir) for 20% less than shell no ethanol 93 (cost 10% more than normal shell premium/93). I drive like 20k miles per year and honestly the additional 500-1000 cost difference per year isn't that much of a concern in the current fuel prices market (I'd care less to pay 4 or 3.79 per gallon). I'm trying to figure out which is the best fuel to use.
The manual recommends 93. I tested 91 and 93...can't tell the difference. Both fuels make the car accelerated the same. I know about engine knocking and how advanced timing works. There doesn't seem to be a perceptial decrease in performance...I'm simply not able to see why don't I just use the cheaper 91 gas. I did notice that the MPG counter is more accurate if I use no ethanol gas...about 10% different, which translates to about 2 MPG for me.
Its a matter of principle. Why should I pay 10% more for normal premium gas which gets me 10% less fuel economy and I notice no performance penalties. Paying more for nothing seems stupid.
I know that west cost only has 91 10% ethanol available and plenty of owners have been using it for years. I think they're fine? I read some posts where they wish they could buy 93, but fact is the car can run on 91 just fine?
I'm in a bit of a dilemma. I can buy 91 no ethanol citgo (top teir) for 20% less than shell no ethanol 93 (cost 10% more than normal shell premium/93). I drive like 20k miles per year and honestly the additional 500-1000 cost difference per year isn't that much of a concern in the current fuel prices market (I'd care less to pay 4 or 3.79 per gallon). I'm trying to figure out which is the best fuel to use.
The manual recommends 93. I tested 91 and 93...can't tell the difference. Both fuels make the car accelerated the same. I know about engine knocking and how advanced timing works. There doesn't seem to be a perceptial decrease in performance...I'm simply not able to see why don't I just use the cheaper 91 gas. I did notice that the MPG counter is more accurate if I use no ethanol gas...about 10% different, which translates to about 2 MPG for me.
Its a matter of principle. Why should I pay 10% more for normal premium gas which gets me 10% less fuel economy and I notice no performance penalties. Paying more for nothing seems stupid.
I know that west cost only has 91 10% ethanol available and plenty of owners have been using it for years. I think they're fine? I read some posts where they wish they could buy 93, but fact is the car can run on 91 just fine?
07-01-2018, 03:54 AM
#4
I was suggested it was better to run 91 non-ethanol than 93/94 with ethanol buy our techs.
Although the car is capable of dealing with up to 10% ethanol it was suggested non-ethanol is more ideal.
Car seems to run just fine.
Although the car is capable of dealing with up to 10% ethanol it was suggested non-ethanol is more ideal.
Car seems to run just fine.
07-01-2018, 09:21 AM
#6
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Where are you located? I seriously doubt you can buy Shell 93 octane without ethanol. I'd love me some of that.
07-01-2018, 09:48 AM
#7
Central NC. I think you're right. Its a Shell gas station on 70 near Hillsborough NC (toward Durham), however I don't think the 93 octane is really Shell gas. The pump is part of a regular Shell pump, but it has separate nozzle for the 93 no ethanol and doesn't have a Shell label on it... just says 'ethanol free' in green. Its probably some other brand, but doesn't say.
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07-01-2018, 09:58 AM
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Originally Posted by minthral
Central NC. I think you're right. Its a Shell gas station on 70 near Hillsborough NC (toward Durham), however I don't think the 93 octane is really Shell gas. The pump is part of a regular Shell pump, but it has separate nozzle for the 93 no ethanol and doesn't have a Shell label on it... just says 'ethanol free' in green. Its probably some other brand, but doesn't say.
Thanks for telling me your location, BTW. I can't see that on the mobile app.
07-01-2018, 10:03 AM
#9
If anyone wondering if using non-ethanol 93 does any magic unicorn stuff to the car... I've used it plenty of times and pretty confident to say no. MPG is better, but not by 10%... maybe 5-7%. It cost 10% more than normal ethanol shell premium, so you don't really save anything.
The Citgo 91 pump clearly marked however. They don't have 93 ethanol premium and the 91 no ethanol instead.
The cost difference between ethanol free 93 and 91 is a substantial 20%+ however.
93: ~3.80
91 ~3.05
Normal ethanol top tier is ~3.20 or ~5% MORE than 91, which has no ethanol, so I assume it will be at least 5% more efficient. So that's 10% savings which results than in paying 100-300 less per year...kinda of a wash in my mind, so the question is which fuel is best for the car.
I also can get E85 for like ~$2 per gallon.
The Citgo 91 pump clearly marked however. They don't have 93 ethanol premium and the 91 no ethanol instead.
The cost difference between ethanol free 93 and 91 is a substantial 20%+ however.
93: ~3.80
91 ~3.05
Normal ethanol top tier is ~3.20 or ~5% MORE than 91, which has no ethanol, so I assume it will be at least 5% more efficient. So that's 10% savings which results than in paying 100-300 less per year...kinda of a wash in my mind, so the question is which fuel is best for the car.
I also can get E85 for like ~$2 per gallon.
07-01-2018, 10:23 AM
#10
Race Director
Minthral, I have a hard time following your logic with all the contradictions and your confusion. I think you like to really bring unnecessary dilemmas into your life.
07-01-2018, 11:00 AM
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Minthral, well, you can't use E85 in the Porsche.
Still, very surprised you have 93 octane ethanol free in your area. I'm still suspect. But since they also have 91 octane ethanol free, I'm a little more believing.
Tell me about your area? Agricultural with farming equipment? Nearby marina? Something is drawing in the corn free 93. What is it? It ain't sports cars.
Still, very surprised you have 93 octane ethanol free in your area. I'm still suspect. But since they also have 91 octane ethanol free, I'm a little more believing.
Tell me about your area? Agricultural with farming equipment? Nearby marina? Something is drawing in the corn free 93. What is it? It ain't sports cars.
Last edited by LexVan; 07-01-2018 at 11:23 AM.
07-01-2018, 11:19 AM
#12
Race Director
If anyplace would have 93 no ethanol would be NC and SC. Not nanny states. Lots agricultural and Nascar (Charlotte). Not sure about marinara?? Maybe at an Italian restaurant 
NC is a great state.
NC is a great state.
07-01-2018, 11:24 AM
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^damn I'm hungry now!
07-01-2018, 11:33 AM
#14
Originally Posted by LexVan
Where are you located? I seriously doubt you can buy Shell 93 octane without ethanol. I'd love me some of that.
Keep the faith!
