I wouldn't mind betting this subject has been discussed before, but having just got my first Cayman - and first car that needs premium grade fuel - perhaps you'll forgive me for asking again what people think is the best petrol in the UK.
I was prompted to wonder after my son (an OCD for anything to do with Astra VXRs, detailed cleaning and performance enhancement) advised me to use Tesco petrol. I was sceptical until he showed me a quote from the following site and a lot of articles on other forums.

"The difference between running 95 Octane fuel and a higher octane fuel from BP or Shell was very noticeable on the open road and the dyno confirmed this, the car did indeed very sluggish on the lower octane fuel. Interestingly the BP Ultimate and Shell Optimax performed almost identically.
But what was nice was the extra gains that Tesco 99 Octane fuel gave over and above the BP and Shell fuels. There was a clear improvement in both torque and power that was both evident on the road and the dyno[url]


http://www.thorneymotorsport.co.uk/tuning/Fuel_Test_Results.shtml

Has anyone had experiences worth sharing?
Dave

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Cayman 2.7, Meteor Grey, Stone Grey Leather, S Alloys & Coloured Crests, Auto Climate, Rear Wipe, Seat Logos, Sport Steering Wheel, Park Assist.

I have not used the Tesco's fuel, normally used Sainsburys High Octane, but recently switched to Shell V-Power for the last 4 tanks worth and I have now seen an improvement in the long distance on the motorway fuel consumption.

Normally on my monthly trip to Truro (Cornwall) from Bristol - 175 miles I use 3/4 tank each way.

Last weekend with Motorway cruising between 85-95 I use only 1/2 tank for 175 miles and the same coming back the other way which included the top down from Exeter and the same cruise speeds.

Please note that this was with my 5 year old Honda S2000, the Cayman S has a May build (I cannot wait), but I would expect similar results.

Were the tests above carried out on a Turbo car?

Jack

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Cayman S - Since December '05

Quote from the article

"As a consequence of our area of expertise it made sense to test cars we knew well so we chose a 2003 BMW E46 M3 CSL, and as a control car a standard Toyota MR2. We are also testing with a 2006 Vauxhall Astra VXR and will release this data when it is finalized."

The VXR is a turbo; so slightly different ruiles apply; 1/2 miles from me there's a BP site selling 102 Octane which is supposed to be fab for turbos, but its £2.45 a litre....

As for your Cayman, I'll pass on what a friend who works in the petrol distribution industry told me (no names, no pack drill). Don't buy supermarket fuel; they source it from any number of suppliers and as a result the quality is variable.

Buy from a well known brand (BP, Shell, Texaco), but make sure its a busy site. Petrol gets stale and this particulary applies to SUL, which is a minority market product.

In a completely unrepresentitive test in my Audi Fsi, the extra mileage I achieved on a tank of SUL more than outweighed the greater cost, and throttle response improved.

FWIW I will go several miles out of my way to buy Shell SUL from a busy site.

SS7

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Carrara white pauper's 2.7
Snickers wrapper in the door bin
Flies on the number plate
Church's scuffs on the kickplate
'Goodwood' umbrella in the back

Have started using Shell V-Power since the last 2 months....
Had filled it up once as a mistake, and immediately noticed a surge in power....no placebo effect, believe me...

since then am totally hooked on V-power...Butt dyno grade it superior to B.P. Ultimate..!!

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