Premium unleaded vs Regular

Why wouldn't you run on the fuel the manufacturer states? As previously mentioned, z4's are fitted with knock sensors so are capable of tuning themselves up (& down) to suit the octane level of the fuel.
It's only a few pence per litre for the higher grade fuel so the apparent saving is negligible & you are losing out on the extra detergent additives as well :fuelfire:
Regards
 
Smartbear said:
It's only a few pence per litre for the higher grade fuel so the apparent saving is negligible & you are losing out on the extra detergent additives as well :fuelfire:
Regards

This is how I look at it. Plus I get double nectar points whenever I do, so they're racking up nicely haha (BP is my closest, though not generally regarded as the best Super Unleaded from what I can tell).
 
Does fuel all come from the same source? Driving through Rotterdam Shell seem to have their own refineries? I'm sure the raw materials / feed stock is all from the same source, but the refining process itself could be different between companies? I'm sure Shell and BP fuel doesn't come from the same refineries?
 
The fuel that goes to various sellers whether it is Shell or Asda must be different.
Years ago I tried using Asdas unleaded and for every £10 I got 15 miles less than using Shells unleaded.
Although Asdas fuel was slightly cheaper it didnt make sense to buy it as I got less miles.
The same goes for using V Power over unleaded at Shell.
I think I worked it out that I would need to get an extra 30 miles out the tank to make it worth while paying the extra for it as there was no real difference felt in performance.
 
I have always run my cars on Tesco Momentum 99 and certainly in my old E36 I saw a massive improvement in MPG and pick up of the engine to using standard fuel so from that moment on I have ran my cars on it.

However in the Zed, I have not used normal fuel, only Momentum so cannot comment on the effects but the way I see it is over a tank full of fuel, it's only a small amount more cost to fill up and yes I understand that over the years it accrues and you could've treated yourself to a weekend away. However using higher octane fuel can only be better for the car in my eyes and the small overhead for that reaps over not using it.

On the contrary, I was watching a car video of our American cousins and they were saying they get crap fuel in places such as 91 Octane - This can only downtune the car as there is less bang.. So surely it works both ways?
 
Since November I have been doing 3K miles a month in my Z (as i had to return my second car) and so been putting standard sainsburys unleaded in (the car is getting chopped in so didnt care so much)

The mpg has been exactly the same on Vpower vs the sainsbury's one! Maybe the performance is down.. but that could be linked to going back to my stock exhaust also!
 
It says in the handbook, i'm to use 97Ron, so why would I not use it. :?

As for Tesco vs Shell. I'm told by Shell, that their fuel has better cleaning agents added and I have no reason to doubt that. Happy to put either in the tank, but 9 times out of 10 it's Shell. The fuel to avoid, IMHO, is the stuff from the local indi, that's been sat in the ground for months. Shame but I stick to forecourts with plenty of custom. :thumbsup:
 
buzyg said:
I'm told by Shell, that their fuel has better cleaning agents added and I have no reason to doubt that.

Would you trust the results of a test that marked by the person who took it? ;)
 
TheHoff said:
buzyg said:
I'm told by Shell, that their fuel has better cleaning agents added and I have no reason to doubt that.

Would you trust the results of a test that marked by the person who took it? ;)

Yes self marking is pretty common, for not critical training. It's not like some one is going to die.

If my personal knowledge & experience demonstrated that it was untrue, then I would have concerns. But they only back up what i'm being told by Shell, so why would I have grounds to doubt what they claim? :thumbsup:
 
buzyg said:
TheHoff said:
buzyg said:
I'm told by Shell, that their fuel has better cleaning agents added and I have no reason to doubt that.

Would you trust the results of a test that marked by the person who took it? ;)

Yes self marking is pretty common, for not critical training. It's not like some one is going to die.

If my personal knowledge & experience demonstrated that it was untrue, then I would have concerns. But they only back up what i'm being told by Shell, so why would I have grounds to doubt what they claim? :thumbsup:

Fairly competitive market place, I'd imagine that they would be pulled up for making false claims.
 
i used to use the standard fuel at Tesco when I first got my zed and my engine seemed to make a slight knocking noise on tickover which was something it wasn't doing when I bought it. since then I have switched to Tesco 99 and the noise has gone but I haven't noticed any difference in performance of economy.
 
buzyg said:
TheHoff said:
buzyg said:
I'm told by Shell, that their fuel has better cleaning agents added and I have no reason to doubt that.

Would you trust the results of a test that marked by the person who took it? ;)

Yes self marking is pretty common, for not critical training. It's not like some one is going to die.

If my personal knowledge & experience demonstrated that it was untrue, then I would have concerns. But they only back up what i'm being told by Shell, so why would I have grounds to doubt what they claim? [emoji106]
The lack of objectivity is what concerns me with a claim such as this - the absence of impartiality would give me a significant reason to suspect the claim is biased in their favour.

This claim may well be true, but it would be unwise to automatically believe it, based upon the information provided by a single employee.
 
Back
Top Bottom