S5 MPG

[R.A.G]

Quick MPG update for anyone considering an S5.

Very impressed with the improvements with MPG as the miles are slowly racking up, with 1800 miles on the clock now, I managed the following on a long (and granted boring) A road run from Herts to Felixstowe this morning.

I genuinely didn't have to try too hard to get to this, just lots of free flowing A roads at national speed limit with a good few sections of solid stop/start traffic in the mix as well.

 

[Ridders71]

That's not bad going. I got around 39 mpg on a 77 mile trip, including climbing over the M62 last week - like you not trying too hard to be frugal, didn't even have it in economy mode- was in auto (though I assume this defaults to economy when driving steadily?). 1200 miles on clock, using Tesco momentum 99 fuel

 

[ChrisH370]

Ridders,
Have you found using 99 fuel improves consumption or do you always use it?
The rating in the fuel cap is 95 so that would seem to be an unnecessary expense, IMO.

 

[R.A.G]

Sorry should have added that's using Shell V Power.

I haven't measured 100% but quite sure I see 3-4 MPG improvement over premium on the higher octane stuff.

I generally use Tesco Momentum too.

 

[Ridders71]

I

Ridders,
Have you found using 99 fuel improves consumption or do you always use it?
The rating in the fuel cap is 95 so that would seem to be an unnecessary expense, IMO.

have filled it with 99 from brand new so not done a comparison. General view on forums seems to be that it does bring slight mpg and possibly even performance benefits. My previous 6 cars were all diesel, so don't have much knowledge on this - to be honest it's more about that phase of ' only the best for my shiney new car'! I am sure the novelty will wear off. I don't do high mileage so not too concerned about price differential

 

[ChrisH370]

Not wishing to go off topic but my experience of owning many cars is that using 99 RON makes no difference at all to the MPG. I tried a couple of tanks of 101 in Germany on the autobahns and it was the same as on 95 and was not hanging about.
I think you've hit the nail on the head, its more about "only the best for my shiney new car". If it makes you feel good do it.
As mine is running-in at the mo I'll be using 95 RON as per the fuel cap. I'll let you know what the mpg is after 500 mms.

 

[Quattro_]

I too at under 1000 miles on the clock have been pretty impressed with the S5's MPG. It is almost as good as the SDV6 Range Rover Sport I had before. I have found that the Predictive Efficiency Assistant makes a big difference. I'm averaging about 28mpg on solely urban driving.

 

[CharlieP]

Do not buy Supermarket fuel imho it is well known not to be as good as the leading brands of fuel for octane levels. Try and stop at shell,bp or Esso supermarkets are cheaper for a reason!

 

[CharlieP]

Back to back dyno runs will prove this

 

[ChrisH370]

As I said elsewhere now mine has done over 1000 mls, I got over 40 mpg on a 250 ml trip.
Has anyone taken their's for a dyno run yet?

 

[KBB]

As I said elsewhere now mine has done over 1000 mls, I got over 40 mpg on a 250 ml trip.
Has anyone taken their's for a dyno run yet?

Wow, thats pretty darn good. Best I had so far is 33mpg on a 300 mile trip, 80% motorway, rest is county roads and a bit of a city traffic. Altho I had about 30 minutes congestion on the motorway part and some "having fun" on country roads.

I'll take mine to a dyno run in a few weeks, I have 1400 miles in the car so I can say its been run in already. Im interested about the result myself too.

 

[cuke2u]

Do not buy Supermarket fuel imho it is well known not to be as good as the leading brands of fuel for octane levels. Try and stop at shell,bp or Esso supermarkets are cheaper for a reason!

Not quite correct as it is more complicated that that, for these reasons:
"They all use the same base fuel, from the same tanks in the same refineries. There are only 6 refineries in the UK manufacturing petroleum distillate, and none of them are for the sole use of one brand. The brands take a tanker full of the same fuel everyone else gets and add a bucket of additive. Shell, Tesco, BP, Jet, Texaco.... they all have a set of additives whose exact formulation is, just like the colonels 11 herbs and spices, a closely guarded secret. These additives include octane boosters, detergents, water, and various stabilisers, but they amount to only a few parts per million in the finished product. The actual fuel is no different, and contains exactly the same amount of energy as everyone else's, and before anyone mentions something daft like Tesco getting BP's cast off low grade fuel that didn't muster, Tesco actually own a sizeable portion of one of the 6 refineries making the fuel, and supply the likes of texaco with it.

The additives were, in years gone by, absolutely essential. Carburettor run engines of poor design and low tolerance needed all the chemical engineering help they could get, but these days the engines are built to such high levels of precision and run with such high levels of control that the only additives really needed are the octane boosters that stop the fuel detonating before the engine wants it to. In this regard the supermarket fuels are as good as any other.

 

[ChrisH370]

Well done for posting this, a tanker driver at Sainsburys once told me he goes to all the well known brand retailers and it's all the same.
And yet people claim their engines run better on Shell, BP or Esso.

 

[ChrisH370]

My last trip was all M'way but due to 50 limit sections (where it was showing 42 mpg) and lucky to do 70, all dangerous bunching due to variable speed limits.
Yes Id be interested to see what figures you get, it certainly feels torquey but I doubt the power is higher than 354 due to max power revs at 6, 500.

 

[CharlieP]

There is a big reason you don't hear about the difference from lab tests and it's because the supermarkets have a very strong legal teams keeping people quite. Ask any tuner and I know what the answer will be. Are you in the petrochemical industry cuke2u?

 

[gldy_b]

I've had my car for over 3 weeks and it has been averaging 20MPG. Today I had a 60 mile round trip and I thought with the weather being bad (heavy rain) I decided to drive in economy and see what I could achieve. Impressed with 36MPG

 

[D T]

What "cuke2u" says makes sense. My cousin used to work as a tanker driver and he confirmed everyone gets the same base petrol/diesel, it's just the additives which differ brand to brand. That having been said he always swore by Shell Super, but that was more to do with its detergent cleaning properties.

Most stock modern cars should be set up to run 95 octane.