[Matthew Boocock]

Being from yorkshire i watch the pennies!!! But, for the first time ever i have just filled up with SUPER UNLEADED!! It cost £53 to fill up but i have read somewhere that after a few tank fulls performance improves.........Thoughts and experiences anyone....

Matt "The Tyke"

[Japper]

Quote: Originally Posted by Matthew Boocock (original)

Being from yorkshire i watch the pennies!!! But, for the first time ever i have just filled up with SUPER UNLEADED!! It cost £53 to fill up but i have read somewhere that after a few tank fulls performance improves.........Thoughts and experiences anyone....

Matt "The Tyke"

Well i've never been a fan of Super Unleaded in the past, but have just started using V-Max after the first 5k miles in my R56JCW was done with std. unleaded. I can tell the difference in performance after a couple of tank fills.

[drb5]

Yep, the fuel burns cleaner and with the ECU learning to use the better fuel, it should give slightly better fuel eceonomy and a raise in performance. Not just power, but smoothness through the revs and better response.

[Fredrik]

Since I got my R56 S I have always used the Shell 99-octane superunleaded fuel.

When I had my previous MINI (Cooper R50), after a few months I changed from the normal unleaded 95 octane to the 99, the first tank was not so big difference, but after a few tanks it was another car - better acceleration, more power (at least it felt like it) and better fuel economy.

I think it gives you a real run for the money, the 99 superunleaded is my choice anyway

[ALD0]

Overall it will be better, if you can justify the extra 4/5 p a litre, go for it.
I run on Tesco Super Unleaded as don't really notice the difference between that and Shell stuff.

[James]

i find that i get better mpg with super unleaded so it doesnt actually work out much more expensive, especially not in the long run as the car will run smoother and itll be better for the engine

[Adit]

I can't say for the mini as yet as I dont have mine yet.... On my smart car I get about 4mpg extra using Shell V power instead of regular unleaded....

[Richard Crofts]

I have to say that my super 97 or some of the other 98s on offer perform as well as V power in my tuned S ... way cheaper too. I just service it regular and run some redex through to keep the deposits down every now and then

[mason storm]

Well I thought I'd give it a go and filled up with Tesco 99, I know VW GTI's do well with it but I'm not sure if the S will adjust to take advantage of the better fuel (something to do with nock sensors whatever that is). I would be interested to know if anyone knows of any official evidence that the S will work better with 99 fuel.

So far it's too early for me to tell but I always thought my S was pretty smooth and powerful anyway so I'm not sure if I'll be able to notice the difference.

[drb5]

A knock sensor hear's the pinking/detonation coming from inside the cylinders. If the pinking/detonation occurs, the ECU retards the ignition and you lose power.....a bad batch of fuel can cause this.

It can take a long time for the ECU to bring the ignition advance back up, but using a higher octane fuel can help this and obviously regain the lost power.

[Mark84]

I've been using shell v-power for nearly 2years now (or optimax as it started out) but my old car had mitsi engine and needed the extra octanes as the engines are built around jap petrol at 100 octane! But you can feel the oomph. havn't tried it in my R50 yet as i have only had the car a week and the dealer filled it up for me! Gonna try v-power again to see what the improvement is like! would always recommend to fill up on it once a month at least to keep the engine clean and the carbon deposits down!

Shell's does seem the best and the only one i have noticed a difference! if i ever used BP or sumthing it didn't feel a smooth! although tesco's wasn't bad! fuel economy does seem to balance the price difference if you drive economoly (yeah right like i'm gonna do that!)

[grodenglaive]

holy cow, you guys get high octane over there. In Canada the regular is only 87 octane and the super is 91.

[drb5]

Ouch! That's low! What horse power is the S over where you are fella?

Problem with getting half-decent fuel, is having to pay for it!

[kmpowell]

Quote: Originally Posted by grodenglaive (original)

holy cow, you guys get high octane over there. In Canada the regular is only 87 octane and the super is 91.

Not quite....

In most countries the "headline" octane shown on the pump is the RON, but in the US and Canada the "headline" number is the average of the RON and the MON (which has an 8 to 10 point difference). This means that the octane in the US/Canada will be about 4 to 5 points lower than the same fuel elsewhere e.g. 87 octane fuel, the "regular" fuel in the US and Canada, would be 91-92 in Europe. European pumps deliver 95 (RON) as "regular" which is the equivalent to 90-91 US (R+M)/2.

[drb5]

Oh right, never knew that. Just presumed what grodenglaive was saying, was the RON.

Learn something new every day.

[grodenglaive]

That's interesting, so it's not a big difference. Our MINIs are rated at 172 hp by the way not 175 like the UK. There are some subtle differences. We don't get the "pop and burble" for instance.

[CHRIS27]

There are lots of different ways to measure the octane value, in the UK we are governed by the BS standards and EN228 (for normal unleaded), this sets out the specification and test methods. In USA and Canada they will have different methods.

It is widely recognised that the fuels over the pond have lower octane values and are slightly cruder but it is not as much as we have discussed (8-10 points). I would guess there is less than 5 in it in reality and the other differences accounted for by the different test methods used.

I work in the petrol industry and thisis known, additionally american and canadian fuels have more particles in therefore a better petrol filter has to be used and this induces more pressuredrop over the fuel system, this will reduce the power of the engine as fuel in the cylinders will be at slightly lower pressure, probably in the region of 1-2psi lower.

[mason storm]

Quote: Originally Posted by grodenglaive (original)

That's interesting, so it's not a big difference. Our MINIs are rated at 172 hp by the way not 175 like the UK. There are some subtle differences. We don't get the "pop and burble" for instance.

I may be wrong but I think mini quote 175hp and 172bhp as these are slightly different measures of power.

[TheBigNewt]

What's the lowest octane you can buy in the UK? In the US it's usually 87. The highest is 93 (in my state it's 91). Of course the Mini recommends 91 octane in ours. I assume it's about 95-96 there. Our 91 octance costs about 15-20 cents more per gallon than 87 octane. I just paid $3.00 for a gallon of 91, which is cheap for the US now.

[Japper]

Quote: Originally Posted by TheBigNewt (original)

What's the lowest octane you can buy in the UK? In the US it's usually 87. The highest is 93 (in my state it's 91). Of course the Mini recommends 91 octane in ours. I assume it's about 95-96 there. Our 91 octance costs about 15-20 cents more per gallon than 87 octane. I just paid $3.00 for a gallon of 91, which is cheap for the US now.

Our std. Unleaded is 95 ron and costs £1.02 per litre ( £4.63 per gallon )

Super unleaded runs from 97-99 ron and costs £1.08 per litre ( £4.90 per gallon )

OR 3 times what you lucky guys pay in the US.