[Dr. J]

I'm sure this has been debated but what *type* of gas is everyone using? 87, 88, 89, 91, 93,... 103? (yes I have seen stations that sell 103!)

I was careful to elaborate on this with my dealer as he said the "manual calls for 89" (before I bought the car). Online I've seen everything from 87 to 91. fueleconomy.gov says "Premium" but that means different things to different people. (I guess "premium" is anything more than 87)

With the actual manual in my hands it says that 91 is "highly recommended" but that the "minimum is 87". I'm still on my first fill up from the dealer and I'm not sure what he put in it.

The incentive is clear - it's roughly a 10 cent bump per grade - and if 91 is not absolutely required, or won't affect the MPG that much then there's no sense in putting in 91. Around here, there's roughly a 10 - 15 cent difference between 89 and 87, then 10 cents more to 91 and perhaps a few pennies to 93 (if the station sells it... usually it's either 91 or 93 but not both).

If regular (87) costs $3.75, that puts 91 at around $4, 7% more. Thus, it makes sense that if you can get a 7+% increase in MPG, filling with 91 makes sense economically.

Thoughts?

[dlpruk]

Don't forget that the knock sensor will retard the ignition - and thus reduce the performance and fuel consumption - if you use lower-grade fuel so it's not just the cost premium to consider.

[MINIAC]

The engine will perform best using 91-93.

[Dr. J]

yeah I know that while the car *can* run on say, 87, there is a performance hit, but the question is - how much of a difference does it make? If the % cost increase is less than the % MPG increase then it' "worth it" economically. There are other factors like engine health/longevity which are harder to quantify.

[Rakey]

Quote: Originally Posted by MINIAC (original)

The engine will perform best using 91-93.

And even better if petrol is used, gas is for cookers and bbq's

[AprilWhine]

Some states even have gas with an octane rating of 94 available, does it do any good to use higher rated gas? I bought some in NJ for my GP but it did not have any noticeable improvements.

[MINIAC]

Quote: Originally Posted by Dr. J (original)

yeah I know that while the car *can* run on say, 87, there is a performance hit, but the question is - how much of a difference does it make? If the % cost increase is less than the % MPG increase then it' "worth it" economically. There are other factors like engine health/longevity which are harder to quantify.

Assuming 10 cents difference between grades of gasoline you're saving yourself only $1.30 (89 octane) or $2.60 (87 octane) per 13 gallon fill-up.

Drink one or two less beers between fill-ups and you and your engine will be better off

[Dr. J]

The only stations we have here are Mobil/Exxon, Citgo, Gulf, Sunoco and Hess - no Shell, Chevron, BP - will it make a difference *which* kind of station I fill up at?

[DaFlake]

Not really, just find a station that you trust and go there.

[Fevs]

Quote: Originally Posted by Rakey (original)

And even better if petrol is used, gas is for cookers and bbq's

or Kurds And any other nation that feels the need to use it !!!!!

[AprilWhine]

Gas is (relatively) cheap, petrol is expensive. That's why I run gas.

[DaFlake]

I have gas...

[CCroker]

According to the manual on my 03 S, it says 91 RON which would be 93 at most pumps as RON is not the stated measure at US filling stations. MINIs will run there best ( performance and fuel wise ) at the better grade. As posted above the differences in prices amount to $1.20 to $2.40 a tank. Fuel injection cleaners cost $5-$6 a can. Plugs cost on average $10 each ($40) and oil and filter costs $40. You will also realize a 1-3 mpg cut in mileage increasing by 1% over each month using the lower grade fuel. So, if you fill up 3 times a week, you will realize an equalization in costs. But, if you fill up just once a week, the increased maintenance will overcome the difference of the cheaper fuel to the more costly correct fuel. If you do your own manintenance you will save again, but if you rely on a dealer or a service center, you've lost $ again. Do what the manual says, but do the services at half the intervals. 7.5K instead of 15K and replace plugs every 2 years not 100K. Plugs are only guarenteed by the manufactures for 2 years. Clean oil lubes better for mpg and use a good synthetic. Don't forget the transmission, manual says for life ( it does have a drain and fill plug). And tires, the most forgotten thing on the ground. Just because the monitor isn't lit doesn't mean you shouldn't check them ( fuel really gets wasted there). Do your maintenance a little more often and you will get more from the MINI and won't have anything to complain about. The MINI is rated #7 in the top 10 Green cars in the US. I can get 28 in town and 38 on highway and still punch it now and then.