[adeuel]

I noticed today while filling up that the gas cap indicates that you should use AKI 93 octane and 91 minimum. 10% max ethanol.

I've always used non-ethanol gas for many reasons, but that only comes in 90 octane.

I don't think I can find anything >90 non-ethanol around here.

So... would you use 91-93 with ethanol or stick to non ethanol at 90??

I haven't noticed any adverse driveability with the 90 non ethanol.

My concern is that I've heard that the ethanol is mixed after production and there can be widely varying percentage content in the fill tanks. Sometimes way over 10%. After seeing what it does to my small engines, I shifted everything over to non-ethanol.

[Fegelein]

Originally Posted by adeuel

I noticed today while filling up that the gas cap indicates that you should use AKI 93 octane and 91 minimum. 10% max ethanol.

I've always used non-ethanol gas for many reasons, but that only comes in 90 octane.

I don't think I can find anything >90 non-ethanol around here.

So... would you use 91-93 with ethanol or stick to non ethanol at 90??

I haven't noticed any adverse driveability with the 90 non ethanol.

My concern is that I've heard that the ethanol is mixed after production and there can be widely varying percentage content in the fill tanks. Sometimes way over 10%. After seeing what it does to my small engines, I shifted everything over to non-ethanol.

I never give this any thought! The only thing i've always made sure to do, was steer clear of the lower tier stations. Only Sunoco and the likes for me. So i always use the 93, like i've done w/ every M, Porsche, Maserati, Mercedes, etc. I own in the present and the past. Also you mentioned small engines? That doesn't apply here.

[norbtx]

I gas up at costco. They only have "may" contains up to 10% ethanol. No problems with any of my cars.

[marcvtec]

This question of ethanol added into gas has alway been a great debate on many forums, some peeps are very anti ethanol as it can cause the engine to run slightly warmer due to the alcohol and put more wear and tear on gaskets, and less milage.
Unfortunately gas companies use the ethanol to achieve a higher octane rating, which is good so less chances of detonation, so some times there is no choice.
Having said that i use sunoco 94 oct ( 10 % ethanol)
I wish shell v-power would make a 94 without the corn - then that would be my go to.

Fun food fact - in 2006 my 335 was one of the first in Canada, and within 5 weeks of driving it and filling it up with 94 octane (10% ethanol) my check engine light came on.
Went to dealer, car was there for 6 weeks, it ended up being the fuel pump was not compatible with the gas.
They flew in a master tech from Germany, which I spoke with. And replaced the bosch pump with an upgraded unit - and heck what do you know bmw usa issued a fuel pump recall 3 years later (i wonder why, lol)

[raym3cs]

i am in jersey so we have 93 octane
some states only have up to 91

i always use 93
even in my Ram Pro Master lol

[Alberta]

I don't understand why you guys don't get 95 or 98 octane.
That's what we have all over in Belgium , France ...

The 95 comes with 10% ethanol , and the 98 with 5%.

Best for our engines is 98.

In Switzerland , I've found 100 octane at a Shell station !

[scotty91ss]

Originally Posted by Can-am

I don't understand why you guys don't get 95 or 98 octane.
That's what we have all over in Belgium , France ...

The 95 comes with 10% ethanol , and the 98 with 5%.

Best for our engines is 98.

In Switzerland , I've found 100 octane at a Shell station !

Easy horsepower, would like to have that here. What is the cost/litre on your 98? Paying $1.34 CAD here for 94 octane (+10%)

[Alberta]

1 liter of 98 is about 1,55€ (2,34 $CAD !!!)
It goes up and down those last few months ...
In France , I payed 1,78€/liter on the highway a month ago.
95 is a little bit cheaper.

[Ryno 27]

X rated!

Costco, 93. Their 93 prices are cheaper than most gas stations 87, and they are top tier fuels

[calpharo]

Out here in California we have horrible fuel options. Best we have access to is 91 octane but all come with up to 10% ethanol to meet our "green" standards.....

I would stay away from Costco. I noticed that when I would use of my wife's 2 previous cars (Yukon Denali and MB GLS 450) that I would experience a rough idle that I never experienced when using any of the brand name fuels

[foldpages]

Originally Posted by Can-am

I don't understand why you guys don't get 95 or 98 octane.
That's what we have all over in Belgium , France ...

The 95 comes with 10% ethanol , and the 98 with 5%.

Best for our engines is 98.

In Switzerland , I've found 100 octane at a Shell station !

Different measurement methods in the US vs Europe:

https://en.wikipedia.org/wiki/Octane_rating

93 in US equals 98 in Europe

[Ryno 27]

I’ve had no issue with Costco gas...

[scotty91ss]

Employee of the Month?

[tcw495]

Is there a reason we don't have higher octane fuel in the US? Especially in parts of Orange County, Beverly Hills, Miami, etc. where you have tons of super cars. I assume there are people that would be willing to pay the premium for that gas.

[utsteve98]

Running lower than 91 may be more detrimental than running up to 10% ethanol. You will lose power and I do not how much the computer will retard timing to compensate for lower octane.

As for why 91 octane is the max in some states. CA has stricter environmental regulations. To increase octane to 93, oil companies added methyl tertiary butyl ether (MTBE). This is quite toxic if it leaked and was banned in CA for environmental concerns. The replacement is ethanol to increase octane. However the infrastructure wasn't set up in CA to handle ethanol also. So they just decreased octane rating.

[foldpages]

Originally Posted by tcw495

Is there a reason we don't have higher octane fuel in the US? Especially in parts of Orange County, Beverly Hills, Miami, etc. where you have tons of super cars. I assume there are people that would be willing to pay the premium for that gas.

Miami has 93 octane readily available at almost every major gas station. Never had an issue finding 93.

[BlueBMWM5CP]

On my M5 Comp gas door it recommends Shell 93 V power nitro+ fuel so that is what I have been using.

[josec70]

93

[tcw495]

Originally Posted by foldpages

Miami has 93 octane readily available at almost every major gas station. Never had an issue finding 93.

I see 93 fairly often...more referring to 95+ (I believe one of the posters above mentioned he can regularly get 98, and I think that was in Europe).

[foldpages]

Originally Posted by tcw495

I see 93 fairly often...more referring to 95+ (I believe one of the posters above mentioned he can regularly get 98, and I think that was in Europe).

See my post above... Europe uses a different measurement system compared to the US. 93 in the US equals 98 in Europe.

[Fegelein]

Originally Posted by norbtx

I gas up at costco. They only have "may" contains up to 10% ethanol. No problems with any of my cars.

I'd only do that in desperation, unless I knew who was supplying them...

[lemetier]

Originally Posted by tcw495

I see 93 fairly often...more referring to 95+ (I believe one of the posters above mentioned he can regularly get 98, and I think that was in Europe).

US along with several other countries use AKI or PON (Anti-Knock Index = RON+MON/2) where as European countries display RON. 93AKI = 98RON. In Miami, there are several stations scattered around that sell 100AKI either at the pump or in containers.

FWIW, the base S63T4 was EPA/CARB certified on Tier 3 87E10 making 599.8 SAE Axle HP. F90 also has Ethanol Sensors incorporated into the fuel delivery system.