Fuel Question

[Cobers Vxr]

Hello Everyone.

I have a question about fuel for a MCS 2003 plate, i always run my last cars on Tesco 99 fuel but now i have a mini will it make any difference over standard?

or will i be better off just running it on normal unleaded fuel?

also if it does make a difference how much?

[The Eggman]

I run on 97 which is all I can get. My tuner said fine but if you have no upgrades then 95 should be fine.

[adam_Randell]

tesco 99 is crap. i ONLY use shell optimax. more mpg, a little more power nothing crazy tho. better for the engine and environment

imo tesco 99 isnt anywhere near otimax (which is 97).

i was at silverstone at MINI united and had to fill up at the BP there...pulled up at the 102ron pump looked at the price and thought id stick to £10 of their 97 untill i could get to shell garage . £2.55 a litre it was!

[Clare_2009x]

Quote: Originally Posted by adam_Randell (original)

tesco 99 is crap. i ONLY use shell optimax. more mpg, a little more power nothing crazy tho. better for the engine and environment

imo tesco 99 isnt anywhere near otimax (which is 97).

i was at silverstone at MINI united and had to fill up at the BP there...pulled up at the 102ron pump looked at the price and thought id stick to £10 of their 97 untill i could get to shell garage . £2.55 a litre it was!

^ That petrol was shockingly expensive

What does all these numbers on fuels mean? (99,97)

[adam_Randell]

its the RON / Octane rating. the higher the number, the more explosive the fuel is.

95 is standard, 97/99 'Super Unleaded' etc etc

[adam_Randell]

Heres a definition, explains it better than me:

Octane rating of a spark ignition engine fuel is the detonation resistance (anti-knock rating) compared to a mixture of iso-octane (2,2,4-trimethylpentane, an isomer of octane) and n-heptane. By definition, iso-octane is assigned an octane rating of 100, and heptane is assigned an octane rating of zero. An 87-octane gasoline, for example, possesses the same anti-knock rating of a mixture of 87% (by volume) iso-octane, and 13% (by volume) n-heptane. This does not mean, however, that the gasoline actually contains these hydrocarbons in these actual proportions. It simply means that it has the same detonation resistance properties as the described 'standard' defined mixture.

[MACKIT]

The numbers indicate the RON rating which stands for Research Octane Number. It's basically a worldwide standard for assigning an octane rating for fuel, which is a measure of resistance of the fuel to detonanate.

Here is a good extract from od faihful Wikipedia:
"The octane rating is a measure of the resistance of gasoline and other fuels to detonation (engine knocking) in spark-ignition internal combustion engines. High-performance engines typically have higher compression ratios and are therefore more prone to detonation, so they require higher octane fuel. A lower-performance engine will not generally perform better with high-octane fuel, since the compression ratio is fixed by the engine design."

[MACKIT]

Doh!! Submitted at the same time.

[Cobers Vxr]

cheers for the replies guys, i will use some sort of super unleaded then?

[M.O.S]

Did you get any more performance running on the 102 then?

[adam_Randell]

Quote: Originally Posted by M.O.S (original)

Did you get any more performance running on the 102 then?

I went for the 97 - couldn't bring myself to pay £2.55 a litre however you would notice a power increase, and it may take a few miles to get the fuel into the sytem properly, and for the ecu to adjust. I wouldn't reccomend putting it in a standard car, as it will get über hot and you could have problems with your head gasket and premature ignition. The challahge cars that were running on it will have cooler spark plugs and the ecu will be mapped to take the bigger bang

[caveman_dave]

Quote: Originally Posted by adam_Randell (original)

its the RON / Octane rating. the higher the number, the more explosive the fuel is.

95 is standard, 97/99 'Super Unleaded' etc etc

95/97 is standard unleaded fuel. 99 is also unleaded (not super unleaded as some supermarkets liked to call it) just as a bit more of a bang allegedly. Super unleaded was designed for 1980's cars that were not designed for unleaded but could have the ingition retarded but required a lead substitute additive to stop the top end melting.

The 102 fuel spec as sold at Silverstone is no good for cars with cats, three or four tanks of such high octane fuel would destroy the cat completely.

Sorry if I telling you how to suck eggs but I have heard too much bull s**t about fuels over the last twenty years, which is less time than I have spent working in the oil/fuel industry.

[PK5]

i think the handbook for the mcs says it best to use 97 rated and the cooper is 95. I hope this helps!

[MACKIT]

Quote: Originally Posted by adam_Randell (original)

I went for the 97 - couldn't bring myself to pay £2.55 a litre however you would notice a power increase, and it may take a few miles to get the fuel into the sytem properly, and for the ecu to adjust. I wouldn't reccomend putting it in a standard car, as it will get über hot and you could have problems with your head gasket and premature ignition. The challahge cars that were running on it will have cooler spark plugs and the ecu will be mapped to take the bigger bang

I remember seeing this 102 RON fuel at a BP garage near Wentworth. Was shocked when i saw the price!! Also it seemed that you had to get a special code from the person at the till to use it.

Coincidentally there was a Ferrari dealer across the road.

I would never put it in my car but i remember reading an issue of EVO that had tried it in various cars. One of the cars was a Porsche 911 Turbo and i think i remember them saying they did a dyno test and it was pushing out an extra 45bhp!! Not bad.

I guess if you can afford a 911 turbo you can afford £2.55+ for fuel!

[M.O.S]

An extra 45bhp If I was ever going to do a track day and had a 911 Turbo I may be interested!