R50/53 Octane Requirements
5th Gear
Joined: Aug 2004
Posts: 1,062
Likes: 1
From: Holden, MA
I was actually told by the SA at my dealership that a rough idle could be cured by switching from super to regular for a tank. I guess what it does is reset the fuel values, essentially the same thing they would do at the dealership.
1st Gear
Joined: Sep 2005
Posts: 14
Likes: 0
Originally Posted by effietn
Hello to all!
I to am new on this site but we do have a 2005 mini cooper s convertible & if we use anything but regular it really acts up! When i try premium it coughs & sputters around. I hope you get to enjoy this wonderful little car as much as we have!
I to am new on this site but we do have a 2005 mini cooper s convertible & if we use anything but regular it really acts up! When i try premium it coughs & sputters around. I hope you get to enjoy this wonderful little car as much as we have!
2nd Gear
Joined: Sep 2005
Posts: 94
Likes: 0
From: Troy, NY
maybe it just depends
Hi all, im waiting for delivery of my '06 MC Cabrio. Part of my decision to buy squeeky 
was fuel savings over my '93 blazer. I did the math, assuming 15k per year traveled, cost of premium fuel being 20 cents more than regular, and checked my milage against what the MINI should get. At the end of the year I should have about $950 
more in my pocket than I otherwise would have. So even the added cost of the premium is a cost savings 
. Its only fun to play with numbers.
MC: 15k/yr / 31mpg = 484 gal/yr * 3.00$/gal = 1548$/yr
Blazer: 15k/yr / 18 mpg = 833 gal/yr * 3.00$/gal = 2500$/yr QED
was fuel savings over my '93 blazer. I did the math, assuming 15k per year traveled, cost of premium fuel being 20 cents more than regular, and checked my milage against what the MINI should get. At the end of the year I should have about $950 more in my pocket than I otherwise would have. So even the added cost of the premium is a cost savings . Its only fun to play with numbers. MC: 15k/yr / 31mpg = 484 gal/yr * 3.00$/gal = 1548$/yr
Blazer: 15k/yr / 18 mpg = 833 gal/yr * 3.00$/gal = 2500$/yr QED
Neutral
Joined: Sep 2005
Posts: 2
Likes: 0
From: Aumsville, Or.
I just switched to mid grade fuel 89 from super 91 and it has gotten rid of my cold start problems. I'll use the super if I'm driving the car hard, but for every day driving on the freeway 89 works just fine.
Just my 0.02 worth
Just my 0.02 worth
1st Gear
Joined: May 2005
Posts: 48
Likes: 0
I went to my "Ultimate MINI Oreintation" monday night and we were told by the SA that preimium is not necessary. The moderator asked the SA - "so if you had a new Cooper S what type of gas would you burn"? answer - "regular"
This is all very confusing to me.
This is all very confusing to me.
Neutral
Joined: Sep 2005
Posts: 1
Likes: 0
Do the Math. Usually Premium fuel is .20 more than regular. As fuel prices go up, and they will keep going up, Premium fuel is not percentage wise that much more than regular. I know I don't type this old, but I remember $.27 per Gallon!!! Your talking MAYBE a buck a tank full,... over the joyful ownership of your Mini, it's MINIscule!!!!!!!! GO FOR IT, Get Motorin'!
1st Gear
Joined: Sep 2005
Posts: 29
Likes: 0
What is Octane
Here is a very good article that explains what the "octane" value means:
http://auto.howstuffworks.com/question90.htm
Here is the important part of the article:
The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, you may have heard of methane, propane and butane. All three of them are hydrocarbons. Methane has just a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbons chained together. It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.
http://auto.howstuffworks.com/question90.htm
Here is the important part of the article:
The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, you may have heard of methane, propane and butane. All three of them are hydrocarbons. Methane has just a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbons chained together. It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.
Originally Posted by DrDiff
But how much will fit in the fuel inlet neck? I like to top it off!
3rd Gear
Joined: Sep 2005
Posts: 220
Likes: 0
From: Orlando, FL
Considering the above information, it would be true to note that 100 Octane would be the max Octane rating? If the Octane # is actually the % Octane of the mix of Octane + Heptane in gasoline? I could have sworn I had heard of 105 Octane gas, or gas rated at over 100 Octane? Maybe I'm mistaken.
4th Gear
Joined: Sep 2005
Posts: 312
Likes: 1
From: NY
Originally Posted by Steeroidz
Considering the above information, it would be true to note that 100 Octane would be the max Octane rating? If the Octane # is actually the % Octane of the mix of Octane + Heptane in gasoline? I could have sworn I had heard of 105 Octane gas, or gas rated at over 100 Octane? Maybe I'm mistaken.
1st Gear
Joined: Jul 2005
Posts: 33
Likes: 0
Neutral
Joined: Nov 2005
Posts: 2
Likes: 0
Originally Posted by geotek
Hi all, im waiting for delivery of my '06 MC Cabrio. Part of my decision to buy squeeky was fuel savings over my '93 blazer. I did the math, assuming 15k per year traveled, cost of premium fuel being 20 cents more than regular, and checked my milage against what the MINI should get. At the end of the year I should have about $950 more in my pocket than I otherwise would have. So even the added cost of the premium is a cost savings . Its only fun to play with numbers.
MC: 15k/yr / 31mpg = 484 gal/yr * 3.00$/gal = 1548$/yr
Blazer: 15k/yr / 18 mpg = 833 gal/yr * 3.00$/gal = 2500$/yr QED
was fuel savings over my '93 blazer. I did the math, assuming 15k per year traveled, cost of premium fuel being 20 cents more than regular, and checked my milage against what the MINI should get. At the end of the year I should have about $950 more in my pocket than I otherwise would have. So even the added cost of the premium is a cost savings . Its only fun to play with numbers. MC: 15k/yr / 31mpg = 484 gal/yr * 3.00$/gal = 1548$/yr
Blazer: 15k/yr / 18 mpg = 833 gal/yr * 3.00$/gal = 2500$/yr QED
: http://www.fueleconomy.gov/feg/findacar.htm
Coordinator :: River City Minis
Joined: Jan 2005
Posts: 649
Likes: 0
From: Richmond, VA
Originally Posted by mcs2nr
while were on the topic...if you put avgas in your mini, will it perform better, since avgas has more led.....because i heard the lead actually gives you the power...is this correct..
1st Gear
Joined: Nov 2005
Posts: 24
Likes: 0
I have a problem, I've been putting 91 in my MCS, but I think my wife was putting 87 in when she filled up. I think she's stopped, but I have a suspicion she still does it on occasion. In any event, the upshot is that we've been using less than 91 for almost a year. Is there any way to clean the engine at this point to restore it to where it should be? The only probelm appears to be a little sluggishness at times.
Coordinator :: River City Minis
Joined: Jan 2005
Posts: 649
Likes: 0
From: Richmond, VA
Originally Posted by frankg
I have a problem, I've been putting 91 in my MCS, but I think my wife was putting 87 in when she filled up. I think she's stopped, but I have a suspicion she still does it on occasion. In any event, the upshot is that we've been using less than 91 for almost a year. Is there any way to clean the engine at this point to restore it to where it should be? The only probelm appears to be a little sluggishness at times.
6th Gear
Joined: Jul 2004
Posts: 2,072
Likes: 4
Originally Posted by ahamos
Just run a few tanks of Chevron Ultimate through, or some similar brand with a bunch of detergents.
Coordinator :: River City Minis
Joined: Jan 2005
Posts: 649
Likes: 0
From: Richmond, VA
Originally Posted by caminifan
Well, I would switch to Chevron Premium (don't knpw about Ultimate, is that a super premium with octane >93?) regardless. However, there is still the potential intake valve deposits from prior bad acts. If it were mine, I would get a container of Chevron Techron fuel additive. Run that along with a full tank of Chevron Premium, and you should be fine. If Chevron gas is not available in your area, check toptiergas.com for gasoline vendors that conform to the Top Tier detergent specification that are located in your area.
6th Gear
Joined: Jul 2004
Posts: 2,072
Likes: 4
Originally Posted by ahamos
Premium, ultimate, whatever. Same stuff, but Chevron gas already has Techron in it, so you shouldn't need to add it. Thus the recommendation to fill up at Chevron a few times.
Originally Posted by frankg
...The only probelm appears to be a little sluggishness at times.
The important consideration going forward is to use a high detergent gas like Chevron all the time.