Almost never. I'm at just over 15k miles (in the last 6 months) my OBC says an average of 42mph and 31.4mpg for the life of the car. I usually get about 450 miles to a tank. I do get a touch better mileage with premium, but on the order of 1-1.5mpg at best (about 25 extra miles to tank.)

That's with a June build MSCm driving the wheels off it, and with the roof rack on most of the time.

 

10 cents different from 87-91? Its around 25 cents different here and that usually equates to 1 gallon a tank difference in cost.

 

Premium (91) Chevron. Hey I can't take the money with me.

 

Premium (91) Chevron every time, without fail.

 

Always Premium, the few bucks you'll save isn't worth the problems you may have from running 87 or 89.

 

^^Exactly.

 

I do wish it could run on regular. The manual says premium because that is what it was designed to run. Who am I to second guess the engineers that designed it? Premium for my MINI.

 

93 octane exclusively. Chevron or Shell

 

MiniDave, glad you pointed out about your low gas mileage right now. Not that I want to turn this into a MPG thread, but I about fell out of my car when I filled up this past week and calculated only 24 mpg (that's by real math, I don't trust the computer). Since I got my car in May, it's usually around 30-31...

 

If it's been cold where you are that can have an adverse effect on mileage. A 6 mpg drop is pretty large though. I usually lose 2 mpg in cold weather.

Back on topic....

Premium gas, always.

 

Or

(10,000miles/25mpg av.)x $.10= (400 gal per year) @ $40 per year to use premium vs. mid grade. If your car get's better gas mileage (less right foot use), it is even cheaper.

Always remember stations stations only have two tanks for gasoline. 94-92 octane and 86-87, and mid-grade is a mix of the two.

 

I always use Premium.

While it may not be as important in a Cooper S, I've also got a oil cooled '89 boxer engine in a '76 911 and it runs cooler in the summer with premium (more complete combustion, in theory)...

 

Shell 93 VPower all the way.

 

I might need all the power the engine can produce at any given moment. I cannot afford to be embarrassed by a competitor hot hatch because I wanted to save $32/year.

 

Yup, '08 literature (and perhaps '07?) apparently says you can run on lower octanes but efficiency and power will be less. The engine can handle it though. MINI being a "world car", according the literature, necessitates this. Note: this seems to be a Prince engine thing.

 

I'd guess the engine would run less spark advance with less octane. Less power because of this. Nice to be able to run regular from time to time. Is the Prince the Peugeot, Citroen, BMW engine?

 

I *always* use at the very least 91, although so far I've been using only 93 from Shell (~4200 miles so far). My rule of thumb is to always use gas from TopTier gas stations (Shell, Texaco, Chevron, etc), and no less than 91. If no TopTier are available, I make do with other gas brands, again nothing less than 91.

Dora wouldn't have it any other way.

 

Cooper '08, and I live in South Florida.

 

Are there any gas brands I should avoid...of the biggies?

And guys, thanks so much for all of the ultra-helpful responses!!!!!!!

 

Regardless of brand, gasoline is a commodity. The brands distribute by tanker trucks from the same distribution facility within a geography.

There are three things to worry about, for those who like to worry:

• Contamination -- usually water from condensation. This is usually the fault of the retailer's storage maintenance, thought obviously problems might be trucked in, too.
• Improper formulation -- usually the fuel truck driver's computerized selections at the distribution facility. (This was my MINI's problem, resolved to my eventual satisfaction via a settlement with the fuel distribution company.)
• Lack of sufficient "detergent" additives -- this is the choice of the brand, though obviously a truck driver making improper selections could also affect this. The Top Tier brands have committed to providing more than the minimum U.S. regulatory requirement, which has been shown to be inadequate. I use Top Tier primarily because of their Ethanol formulation restrictions.

 

My 07 MCS manual says that lower octane can be used, but I just use Premium, 91 is the highest I can get in CA. I drive conservatively most of time, too much traffic going and coming from work to drive fast anyways.

 

91 octane is the highest we can get in San Diego County (except for one gas station in Rancho Santa Fe where they carry 93 for the Ferraris, etc.). It's all I've ever put in my MCS...

 

Only gas with the highest ethanol content for me.

 

94 whenever I can get it. 91 otherwise. -

 

hey i live in Miami so, stick with the 93 you can get from shell, chevron, citgo and bp. dont trust any of those like westar and u gas things down here lol. i drive up to plantation every day for work and honestly the price difference is only 10 cents and you get better performance and mileage out of the premium.