[MN]

Hi Guys

Had to fill up the car today after the half tank given by the dealer almost ran out. Filled up using Tesco Momentum 99 which is what I used in the 330e.

However, I noticed a difference as I took it for a stretch on the motorway and country roads. Seems like the car is lacking the poke it had with the other fuel. Only had it for a week so I thought I’d ask what you guys use in your 540i’s.

Many thanks

[MN]

I should add that I’m in the UK 🇬🇧 😊

[ADS-UK]

Originally Posted by MN

I should add that I’m in the UK

Never felt any difference with various fuel types over the years. I've subsequently settled on using whatever the cheapest at pumps.

[MN]

Originally Posted by ADS-UK

Never felt any difference with various fuel types over the years. I've subsequently settled on using whatever the cheapest at pumps.

I’ve been doing some reading and found that Tesco 99 has more ethanol but lacks the other additives such as the cleaning agents etc

Given that today was a warm day that could be a factor but I doubt it. I think I will have to try Shell VPower and see how that goes.

[babaikram]

What I have read is that high performance engines do perform better with premium fuels. I would surely categorise B58 engine as a high performance engine. I noticed that my former F10 N47 4 -POT engines did perform better on Esso fuels more-so with their premium fuels.

I have only been using COSTCO premium fuels in my current cars so would not be able to comment much.

[emre]

As the government sets a “maximum price” for fuel and no one is allowed to sell above that, 95(RON) and 97(RON) are the only options here.
No more 98 or 100 like in the past.

I have had my car for almost a year and I always go with 97. I have had 3 cases I had to fill 95(RON), first was in the first month of ownership when the car was bone stock and felt no difference at all.
The other 2 times were after MPPSK install and I could feel car was not pulling as strong. Nothing major but easily noticeable.

[AP]

posting this video from Fifth Gear (UK) some years ago that compared different fuels on a VW Golf

Talking purely about performance and ignoring any other benefit the fuel may have such as cleaning, there is not a lot of difference in HP that the cars produced.

From what I understand the higher compression ratio the engine the more benefit that a higher octane fuel can have. the 540i is 11:1 I believe so fairly high compression as I understand it. (the E39 530i I believe was 11.5:1)

I'm not sure I could recognize in driving the difference in HP that occurs if this video is anything to go by although of course we're talking about a B58 engine here so it could potentially be different . Technically speaking I'm sure there is a difference but it surely is so small , can we really pick up on that?

The manual states you can use regular or premium. In contrast the E39 530i I had which had a higher compression ratio recommended premium fuel (although of course it would work on lower)

Guess make your own mind on this.

[MN]

Thanks guys. Will have to drive the car today to see how it feels and then try Shell fuel

[ztx84]

I've so far stuck with standard Esso/BP 95... Thought about running the higher octane stuff in my 540 but haven't experimented yet. I don't run supermarket fuel in my cars (a habit of mine since I started driving!)... but it seems perfectly happy on standard 95.

[JOHNBMWM5]

I have the M performance Kit so use 97/99 Fuels all the time, I find the car runs/pulls better on it. IF you compare the MPG of both fuels ie 95 vs 99/97 (I Did) you will find the higher octain gives slightly better MPG outweighing the cost difference, SO put the good stuff in IMO.
On average it would be 13Pence difference a gallon UK, if you get even one or two MPG more you win.

[MN]

Originally Posted by JOHNBMWM5

I have the M performance Kit so use 97/99 Fuels all the time, I find the car runs/pulls better on it. IF you compare the MPG of both fuels ie 95 vs 99/97 (I Did) you will find the higher octain gives slightly better MPG outweighing the cost difference, SO put the good stuff in IMO.
On average it would be 13Pence difference a gallon UK, if you get even one or two MPG more you win.

Thanks for that. What baffles me is why the car felt different (less impressive) on the momentum 99. Maybe it’s just me but I doubt it. A hot day like yesterday shouldn’t have that much of a bearing too.

[HighlandPete]

Originally Posted by JOHNBMWM5

On average it would be 13Pence difference a gallon UK, if you get even one or two MPG more you win.

10 - 13 pence a litre difference up here, 95 vs. 97 RON.

No 98/99 locally, so hard to justify the price of 'just' 97 for typical local driving.

I have found 99 does give a definite difference in driving feel and responsiveness in the N55 engine. Better mpg, if not using the added performance.

I recall one of the tuning companies testing fuels on a dyno. The higher the performance the greater the gain between 95 and 99. A Toyota MR2 gave over 5% increase in BHP. A tuned BMW E46 M3 CSL ran something like a 10% improvement, (~40BHP) on 99 compared to 95 RON fuel.

[ztx84]

Originally Posted by MN

Thanks for that. What baffles me is why the car felt different (less impressive) on the momentum 99. Maybe it’s just me but I doubt it. A hot day like yesterday shouldn’t have that much of a bearing too.

That is a bit of a weird one... It might be temperature related you know (at least a bit). Turbo engines love cold weather and with this recent spike in temps it may affect power a little bit, although the water/air intercooler in the B58 should in theory minimise that anyway. In previous cars I have noticed they pull a bit better in colder weather...

As an aside a relative of mine who works as a mechanic was very impressed with the air/water intercooling on the engine - he said it looked a proper piece of kit!

[Dephead2004]

Here's another

[MN]

Originally Posted by ztx84

That is a bit of a weird one... It might be temperature related you know (at least a bit). Turbo engines love cold weather and with this recent spike in temps it may affect power a little bit, although the water/air intercooler in the B58 should in theory minimise that anyway. In previous cars I have noticed they pull a bit better in colder weather...

As an aside a relative of mine who works as a mechanic was very impressed with the air/water intercooling on the engine - he said it looked a proper piece of kit!

Many thanks for that and video. I’ll take it out for a spin later today and see how it feels otherwise burn this load and hit the optimax!