How many times? Because it has more octane in it which the FSI engine is designed to run on (runs for longer in FSI mode, this has all been said and I cant be assed to find the link). It has cleaning agents in which help keep your engine cleaner, thus more efficient. You get more MPG. Your meant to get more power (all be not much) etc etc etc. You just have to decide if you want to spend that bit more on your fuel or not, it will run perfectly well on 95.
But you seem to be forgetting that Audi have developed the latest TSI Mk6 engine to now achieve maximum economy with just 95 RON. So by simply slinging 99 at it will NOT give you any further improvements in fuel economy. The ONLY time using 99 would give improvements in power and/or economy is if it was remaped.
You see my confusion?
Rolfe.
Huh - AlanD was quoting from how the Mk5 GTI was set up, whereas my answer was for the Mk6!
So in a Mk6 GTI - max economy will be gained with 95 RON.
Well, at least this looks like a reasonably definitive answer.
I have no idea at all why Alan was quoting from how the Mk5 was set up, in his (rather tetchy) answer to me who has a Mk6 on order (which is kind of why I was asking in the Mk6 forum), but we seem to be clearer now.
Well to be fair to Alan, he was probably just presuming that the Mk6 engine would be set up exactly the same as the Mk5 - afterall, they both use FSI and turbos. And technology doesn't usually take a 'step backwards'.
All entirely innocent, if a little misguided. And Alan isn't usually 'tetchy' either - maybe he was just having a bad day?
So, no advantage in fuel economy, and am I also right that there's no power advantage? Or might there be?
Correct on both counts. The only time that using a higher octane on the Mk6 will give you more power is if you had it remapped.
And it's debatable whether there might be an advantage in cleaning the engine, but probably not much difference if one uses quality branded 95 RON rather than cheap supermarket own-brands (excluding Tesco's own brand, which is rocket juice).
Am I getting it?
Rolfe.
Corrected your typo!
Ohh, the super unleadeds
will be slightly better at cleaning your engines innards, but by how much - that is the difficult question - and purely on the 'cleaning' issue, is difficult to give concrete answer. However, my own personal advice for the Mk6 would be to use normal 95 from the majors or Tesco, but every 4th tankfull, use any of the super unleadeds (and it wouldn't have to be just the 99 RON brews either - BP, Total, Esso - should all be fine).
HTH.
