[RealDwC]

Forgive my ignorance, I just purchased my first BMW 2 weeks ago (320i xDrive Sport). I filled up for the first time today, and I went with Petro-Canada Ultra 94. I've seen some mixed feelings on this, and was curious to know if there is anything to be concerned about, or at least keep an eye on?

If I were to switch back to 91 octane at 1/4 tank left of the 94 is that okay?

Any help is much appreciated.

[azuritschwarz]

Anything 91 octane & over is allowed to be pumped, doesn't really make a difference if you have 30% 94 & 70% 91 in your tank, or vice versa.

Happy driving!

[the dope steez]

The petro 94 is pretty good. I use that in the summer and run the bm3 93 octane tune. Not perfect timing leading me to believe the fuel quality is not the best but it does the trick.
In winter I just run Costco 91 because it's cheap and ethanol free.

[BEAR-AvHistory]

Good gas would run it all the time if it was available here. Our premium is 93.

[RealDwC]

Originally Posted by the dope steez

In winter I just run Costco 91 because it's cheap and ethanol free.

Thanks for this. I was curious about a winter gas strategy. Will probably run 91 for the rest of the winter.

[eluded]

In Cali we only have 91 craptane

[BEAR-AvHistory]

Originally Posted by RealDwC

Thanks for this. I was curious about a winter gas strategy. Will probably run 91 for the rest of the winter.

Are you aware to get more power out of the turbo a mix of premium & E85 is known as "poor mans racing gas"

Personally have the option of 87/89/90 no ethanol/93/100. I always run 93 in the 440. When I had the JB4 tuned 335is I ran at 50/50 93/100 mix or a 70/30 93/E85 mix. Track was straight 100 on MAP7

[RealDwC]

Originally Posted by BEAR-AvHistory

Are you aware to get more power out of the turbo a mix of premium & E85 is known as "poor mans racing gas"

Personally have the option of 87/89/90 no ethanol/93/100. I always run 93 in the 440. When I had the JB4 tuned 335is I ran at 50/50 93/100 mix or a 70/30 93/E85 mix.

I'm not aware of much when it comes to BMWs, or truthfully, cars in general.

What I do know is it's a helluva lot more fun driving, and I'm looking forward to the summer.

[5ilver-5amurai]

Running mixes of 91+ octane in your tank from fill up to fill up should have 0 negative impact on your engine. I ran 94 for 6 years, but recently started running 91 from another station. I feel that there is virtually 0 performance or mileage gain to 94 - according to my butt dyno at least. I know some people fill up on 94 when they have certain tunes, but I'm not a tuner.

[jcordier]

Originally Posted by eluded

In Cali we only have 91 craptane

We can get 100 octane aso

[Billfitz]

Originally Posted by RealDwC

I'm not aware of much when it comes to BMWs, or truthfully, cars in general.

If you don't have a high compression engine running with advanced timing and/or high boost pressures there's no benefit from running more than 91 octane, and if you don't drive aggressively no advantage to more than 89 octane. I can't speak to how you drive, but a 320 does not have a high compression engine running with advanced timing and high boost pressures. That's not what gasoline company advertising, or those who believe gasoline company advertising, will tell you. It is what you'll find at sources that have nothing to gain by convincing you to spend more than you need to.

https://www.consumer.ftc.gov/article...ctane-gasoline

[BMWILUVU]

91 is probably the lowest octane I would run on an N20. If 94 feels smoother I would go with that. N20 runs lower boost but that and plus the mechanical compression means it still sees high effective compression.

[BEAR-AvHistory]

Originally Posted by jcordier

We can get 100 octane aso

Different measuring system Euro 100 is the rough equivalent to USA 94.

[jcordier]

Originally Posted by BEAR-AvHistory

Different measuring system Euro 100 is the rough equivalent to USA 94.

So, this is really just 94? I'm really not sure now. I figured it was actually 100.

[BEAR-AvHistory]

Originally Posted by jcordier

So, this is really just 94? I'm really not sure now. I figured it was actually 100.

Pump is the English with the US system so its 100. The Cyprus is an island country in the Eastern Mediterranean uses the Euro system so 100 would be 94.

[jcordier]

Originally Posted by BEAR-AvHistory

Pump is the English with the US system so its 100. The Cyprus is an island country in the Eastern Mediterranean uses the Euro system so 100 would be 94.

Thank you. I learn something new every day.

[BEAR-AvHistory]

Originally Posted by jcordier

Thank you. I learn something new every day.

No problem, my bad for not checking your location spelling. DUH

Quick definition

Most common type of octane rating worldwide is the Research Octane Number (RON).

Another type of octane rating is called Motor Octane Number (MON).

Just to show its individuality ours is called Anti Knock Index (AKI)

AKI is (RON + Mon)/2.

Don't ask, have no idea why we do it that way. But the end result is our numbers on the pump officially (AKI) Anti Knock Index, but sometimes called Pump Octane Number (PON), just to make it more confusing, will always be lower then the straight RON octane number for the same gas.

Lived in England for a time so got used to both systems.

[Musashi]

Originally Posted by RealDwC

Forgive my ignorance, I just purchased my first BMW 2 weeks ago (320i xDrive Sport). I filled up for the first time today, and I went with Petro-Canada Ultra 94. I've seen some mixed feelings on this, and was curious to know if there is anything to be concerned about, or at least keep an eye on?

If I were to switch back to 91 octane at 1/4 tank left of the 94 is that okay?

Any help is much appreciated.

The best thing you can do for your engine is use ethanol free gas, 91 Shell or Esso- be it unsure if Esso is ethanol free.

[F36GC_NYC]

Originally Posted by Musashi

The best thing you can do for your engine is use ethanol free gas, 91 Shell or Esso- be it unsure if Esso is ethanol free.

how about BP?

[Musashi]

Originally Posted by F36GC_NYC

how about BP?

Grab a sample and test, look for water separation. I do not know nor do I trust gas stations. I do trust Shell. Today I used for the first time Petro Canada 94 in 6 years, to "clean" the current set of spark plugs and inside the cylinder. After that am sticking to V Power.

[agentorange]

Not only are we limited to 91 octane because our gas comes from CA, but all the standard gas vendors involve some ethanol by law October to March. Who knows if they actually change the brew in the summer.

https://www.clarkcountynv.gov/airqua...3_07-01-04.pdf