Unleaded vs Superunleaded

[RichardG]

I know most forum members are advocates of superunleaded so recently I decided to make the switch, as I have previously stated I have owned my Zed since new for just over 6 years now and it currently has 54K on the clock.

The Zed is parked up for long periods when I'm away with work but when I'm home it's first run usually lasts a couple of hours back accross the A66, M6 and A75 from my parents (where I've left it) to my home in Castle Douglas. Then it's a mixture of pottering about the local area coupled usually with a run to see friends or family scattered the length and breadth of the country.

So I would say that over the last few periods at home I have covered 1500 - 2000ish miles on superunleaded, should this be long enough to see any benefits if any? My observations are; that the Zed does not seem to run different and actually seems to use more fuel and as such I am seriously considering returning to normal unleaded given the price differential.

I have a 2004 2.5SE, is it this engine is just not as highly strung as the bigger engines and therefore does make the best use of the higher octane rating.

Any thoughts or opinions greatly appreciated.

[pvr]

On my previous 3.0, I had little choice as the engine was pinking like mad on normal unleaded. I am surprised to hear that your consumption went UP as the norm is that on the higher octane, the consumption should go down ...

[bigshurv]

My 3.0 runs fine on normal unleaded,and in reality I cannot tell the difference.I've read that mine makes 231bhp on the good stuff and 221bhp on the cooking variety.I don't know if this is true or not.I still run it on Shell v-max as the book says to run it on a higher octane fuel.I'm sure others will have different tales to tell.

[Sticks]

I find the V Power makes a little difference, though I wouldn't use supermarket fuel.

Not sure if this just applies to the auto, but the way the car 'adapts to your driving style' makes more difference, as I've found recently since my useage changed. It can be reset by switching on ignition, press accelerator to floor, swith off.

Or just try an Italian tune-up?

[pvr]

switching on ignition, press accelerator to floor, swith off.

Isn't that a normal outing in the car?

[ranski]

I think sticks is right, but you only turn the key to the first 'click' then depress the peddle

[RichardG]

I tend to use Shell the vast majority of the time, also helps there is no supermarket fuel within 15 miles of where I live.

[noxas]

I have a 06 3.0si which I run on Tesco Super unleaded 99ron (or Momentum as they now call it) since switching from 95ron fuel consumption improved by about 5%.
The car feels sharper and the throttle response feels brisker, how much of this is me looking for a change I don't know?.
IMO the 99ron costs more but you go further so no change in cost, as to the sharper feel I don't know, as this is not some thing I can measure it's just seat of the pants.

The link below is some info on Tesco fuel

http://www.petrolprices.com/greenergy.html

[BMWZ4MC]

I use Shell V power as a routine, but I will use Tesco 99 octane fuel if I'm not near a Shell station. Higher octane fuel makes an easily detectable difference to throttle response in the ///M. Also, there is perhaps a slight increase in max rpm, certainly it revs more freely. Interestingly, Tesco fuel seems to lead to slightly smoother running at mid-range revs compared to Shell. I continue to use Shell and try to avoid Tesco fuel anyway, as I've had a bad experience previously with supermarket fuel.

[cj10jeeper]

Been running on Tesco 99 for 3 years now. Clear improvement in response and increased mpg easily covers the extra few pence.

Of course real difficult to prove given the unreliability of the butt dyno and natural desire to change driving style.

I notice it mostly when I have to fill up with cr*p somewhere else and the car feels lame.

[gannet]

I might have to give tesco 99 a try then...

been running on shell v power (or whatever they call it now) for a long while and noticed the difference in feel straight away.

Can't say I've noticed much difference in consumption though...

[tomTVR]

I personally can't tell the difference, probably not a good enough driver. But i always use super, i even did a 3000 mile road trip last month around Europe and managed to avoid putting any 95 in at all.

Here my logic: Petrol is the primary thing you put into your pride and joy. At 10,000 miles PA and 30mpg average with V-power costing 5p per litre more, its costing me an extra £76 a year. In the scheme of things and compared to what i spend on other tat, it seems a tiny price to pay to know my car is getting the best. Thats not including the mpg improvement so i think you can realistically half that number, so it really isnt much at all. Just remember that most (if not all?) supermarket super doesn't contain the beneficial additives of V-power, Ultimate etc.

I did read on here that it takes about 3 tanks of the super (going from regular) for the ECU to adapt to higher octane so there doesn't seem much point in switching between the two often - you need to stick with it to see the benefits.

[Smokin]

Shell V-Power. I also get better mileage using it over lower octane. I think more important than octane, though, is level of detergent. Cheap gasoline without a good additive package can add to deposits and gunk.

[ksher]

Shell V-Power all the time.

[Z4 Beemer]

Shell V-Power all the time.

Is 95 not the recommended fuel for the E89 (from sticker inside fuel flap)...?