Using a lower octane fuel than recommended
- Thread starter The Critic
- Start date
I actually think it's Shell or a Shell station I occasionally go to that says on their pump that V-Power grade doesn't contain ethanol.
Zee09
$200 Site Donor 2023
Yeah here 91 saves you only 10 cents. I think Sunoco is the only one around here that offers 91...
93 is everywhere.
Zee09
$200 Site Donor 2023
All gasoline brands have both pure and ethanol-containing gasoline under the same brand names. For example, Shell V-Power ranges from 91 to 93 octane both with and without added ethanol. It just varies from station to station, and it's up to the station owner whether or not to sell pure gas.
I just read this now....my station does not carry the ethanol free.
The ecu can only pull some much timing. Why risk damaging a piston to save $0.10 a gallon?
regular gas stations here... .60-1.10 per gallon. and the ECU can pull plenty of timing.
I wouldnt use less than the "REQUIRED" octane.. but doesnt mean you have to use the "Recommended" octane either.
Mostly yes and any octane rating can have ethanol or be ethanol free. Unless of course you live in an area where oxygenates are mandated (like I do) then it is illegal to sell straight gasoline.
wemay
Site Donor 2023
No
More like, sixty cents a gallon, times what? twenty gallons a week times 50 plus weeks a year. Adds up like anything else.
Says the guy who has to own anything needing high octane…
Yep summit county ugh. (akron ohio area)
Here can only buy it as Canned, recreation, or marina gas. usually 90 octane.
Here we can’t buy E0 anywhere even at the Milwaukee Marina.
Zee09
$200 Site Donor 2023
Here in MD. according to GasBuddy we have 96 cents spread in a 20 miles radius just for 93 octanes alone.
JHZR2
Staff member
I had a chipped BMW, older model, which it was recommended to me to not go below 91. My Saab had some info to the extent that it was ok to stray from the 91 recommendation, because though it is a turbo, it’s a low pressure, low inertia turbo, and engine controls would manage.
On the 135i I run premium no matter what because it’s too $$ to find out the hard way.
I would occasionally blend 93 and 87 on my Saab because it was tuned to only need 89 or 91. This was primarily on long trips when it was convenient to top up when stopping to stretch legs. We didn’t do so very much.
I did run 87 straight for a few tanks vs 93 and didn’t find an mpg difference. But the savings of running regular these days can be big.
On the 135i I run premium no matter what because it’s too $$ to find out the hard way.
I would occasionally blend 93 and 87 on my Saab because it was tuned to only need 89 or 91. This was primarily on long trips when it was convenient to top up when stopping to stretch legs. We didn’t do so very much.
I did run 87 straight for a few tanks vs 93 and didn’t find an mpg difference. But the savings of running regular these days can be big.
manicrodder
$50 site donor 2022
We have 85 octane at the pumps due to our higher elevation which most use without apparent incident. I still use 87 miimum.
Maybe in high elevation areas, where the 87 AKI got promoted to mid-grade and 85 AKI is standard. If it was my old car... I would have used 91 AKI regardless (turbo motor, tuned for 91 AKI)
Tried it on a few cars, and mileage always suffered, so not worth it.
I've seen some interesting pumps. Over the summer while driving through MD I filled up with Super 88, which is an E15 blend since it was about 10c/gallon cheaper than regular 87 and it was a model 21 model year car. There was no noticeable decrease in fuel economy for that tank (all highway) compared to normal.
I run 87 octane in my 2006 Volvo S40 T5
Volvo recommends premium fuel for best performance, but using 87 octane will not affect engine reliability.
Volvo engines are designed to achieve rated horsepower, torque, and fuel economy performance using premium 91 octane fuel.
Volvo recommends premium fuel for best performance, but using 87 octane will not affect engine reliability.
Volvo engines are designed to achieve rated horsepower, torque, and fuel economy performance using premium 91 octane fuel.
We run my son's '08 Lexus RX350 with 87 and it calls for 91...he's a teenager and this saves him some money. Runs just fine. There is no way you are making up the price difference per gallon for the slight efficiency drop here from not optimizing ignition advance. Driveability is fine but he's not beating on it...if he were going up into the mountains I'd say run the higher octane. Before we got it from my folks my dad always ran 89 unless the mountain type scenario was there. 14 years old/136K mi.
My two VWs both take higher octane fuel. I run the Sportwagen on 93 plus a few gal of E85 if I want max performance (it's running aftermarket software for 93 but this cars loves some corn to zero the KR/max advance plus cooler combustion) and the W8 calls for 91 min. Atlas runs happily on 87. Focus is aftermarket-tuned to take advantage of 93.
I have some interesting logs from the Atlas of timing correction running both 87 (min. required) and 93...will post in am.
My two VWs both take higher octane fuel. I run the Sportwagen on 93 plus a few gal of E85 if I want max performance (it's running aftermarket software for 93 but this cars loves some corn to zero the KR/max advance plus cooler combustion) and the W8 calls for 91 min. Atlas runs happily on 87. Focus is aftermarket-tuned to take advantage of 93.
I have some interesting logs from the Atlas of timing correction running both 87 (min. required) and 93...will post in am.
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So rather than speculate, fall victim to placebo and butt dyno, or fall for internet boogeyman on this subject I just collect data. Here's the timing correction logs for my VW Atlas on 87 vs. 93. VW states 87 is min. required octane. Both Costco fuels. Both in similar enviro conditions. Both same test...2 to 3rd gear pull to redline on same stretch of road. See if you can guess which is which. I still run 87 b/c the money isn't justified on my wife's daily around-town vehicle but you are going to make a little more top-end power on that 3.6 VR6 on 93 which jives with owner's manual comments to the effect that *performance numbers achieved using premium fuel.
So for those saying any timing/knock correction is bad/don't skimp out on your gas...how does that work when you get KR on 93? I think most folks have no idea how their vehicle looks w/r to KR and the fuel they use and if our cars were that sensitive to fuel there would be a lot of blown engines...but there aren't.
So for those saying any timing/knock correction is bad/don't skimp out on your gas...how does that work when you get KR on 93? I think most folks have no idea how their vehicle looks w/r to KR and the fuel they use and if our cars were that sensitive to fuel there would be a lot of blown engines...but there aren't.
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