981 + super unleaded?
981 + super unleaded?
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Discussion

nickv8

Original Poster:

1,442 posts

106 months

Monday 22nd March 2021
quotequote all
Hi all - not that many chances to fill up the 2015 Boxster S since I bought it in December, but so far I’ve stuck to super unleaded. That’s what’s in the book and filler cap.

Bypassing any additional performance benefits (I wouldn’t notice going by past cars), do many owners bother stick to super or just default to normal?

Thanks!

anonymous-user

77 months

Monday 22nd March 2021
quotequote all
If you want to be able to use the full performance potential of the car you need to run it on super. If you're not bothered, the other stuff will work just fine.

domster

8,431 posts

293 months

Monday 22nd March 2021
quotequote all
I chuck Super in the 981 2.7 we have. Porsche seemed to recommend it and probably runs a bit cleaner. It's a weekend toy though so it's an easier choice to make than if hacking up and down motorways at under 3k revs.

DJMC

3,584 posts

126 months

Monday 22nd March 2021
quotequote all
Not just any Super.
Shell first choice.
Only BP or Texaco otherwise.
Don't touch supermarket stuff. Learnt from experience they are NOT all the same.

Lonely

1,099 posts

191 months

Monday 22nd March 2021
quotequote all
DJMC said:
Not just any Super.
Shell first choice.
Only BP or Texaco otherwise.
Don't touch supermarket stuff. Learnt from experience they are NOT all the same.
I'd be interested to know what your experience was if you have time.

I've owned my Gen 1 Cayman S for 11 years now (it's a 14 yr old car) and yes, it's the one the internet hates for fear of the engine exploding if you so much as look at it! Only used as a 2nd car so relatively low mileage. Never been tracked but does get a decent drive when I do use it! Only ever put Tesco super unleaded in it as it's nearby and it goes ok for me.

Am I missing something or is this a whole new debating area?

Orangecurry

7,764 posts

229 months

Monday 22nd March 2021
quotequote all
Probably.

Almost all fuel today, in ANY petrol station, comes from the nearest distribution centre (DC).

So let's be clear - it's all the same base fuel.

Each branded tanker arrives at the DC, fills up, and then adds it's own unique additives package. That's the only difference. Shell included.

Oddly now Esso is promising E0 in their super-unleaded, but again this is geographically limited, due to what is available at the nearest DC.

Greenery currently supply a large swathe of Esso branded petrol stations. Greenergy have always supplied Tesco 99.

So it's all down to the tanker drivers' magic-mix.

https://www.greenergy.com/greenergy-becomes-fuel-s...

ETA
https://www.tesco.com/help/petrol-stations/

Under UK legislation, large fuel producers have a mandatory obligation to use a certain percentage of fuel from renewable sources. The renewable fuel used in petrol is ethanol, typically produced from sugar or starch crops such as sugar cane and maize. Dependent on location and supplier, UK petrol contains between 0 and 5 percent ethanol (produced in compliance to BS EN 288:2012).


Edited by Orangecurry on Monday 22 March 18:28

HighwayStar

4,824 posts

167 months

Monday 22nd March 2021
quotequote all
Lonely said:
DJMC said:
Not just any Super.
Shell first choice.
Only BP or Texaco otherwise.
Don't touch supermarket stuff. Learnt from experience they are NOT all the same.
I'd be interested to know what your experience was if you have time.

I've owned my Gen 1 Cayman S for 11 years now (it's a 14 yr old car) and yes, it's the one the internet hates for fear of the engine exploding if you so much as look at it! Only used as a 2nd car so relatively low mileage. Never been tracked but does get a decent drive when I do use it! Only ever put Tesco super unleaded in it as it's nearby and it goes ok for me.

Am I missing something or is this a whole new debating area?
The fuel going in the tankers is the same, it’s the additives that the various companies add that that varies between Shell, BP, Tesco’s etc.. Shell V power is generally believed to be the best available super unleaded. I could waffle but here it is...

https://www.shell.co.uk/motorist/v-power-fuels/v-p...

My 981 CS has only had Shell VP in so can’t comment re performance but... When I started using VP in my previous Audi TTS performance noticeably improved and economy was a few mpg better. The economy was neither here nor there for me, VP costs more. Personally, I’d always use it in a performance car.


nickv8

Original Poster:

1,442 posts

106 months

Monday 22nd March 2021
quotequote all
Cheers, all.

My only test with Super on a performance car was with my previous V8 Vantage S. I tried it with both, and it resulted in zero difference. Aston also suggest super, but when I talked to service at the dealer, they said not to bother.

So long as using a lower RON rating doesn't affect some hardware, I think it's back to normal unleaded. Doubt I'll notice 0.05 seconds difference to 60 wink

Orangecurry

7,764 posts

229 months

Monday 22nd March 2021
quotequote all
nickv8 said:
Cheers, all.

My only test with Super on a performance car was with my previous V8 Vantage S. I tried it with both, and it resulted in zero difference. Aston also suggest super, but when I talked to service at the dealer, they said not to bother.

So long as using a lower RON rating doesn't affect some hardware, I think it's back to normal unleaded. Doubt I'll notice 0.05 seconds difference to 60 wink
Performance aside, I'll add that on a car with a dynamic/adaptive ECU, same as yours, with RON 99 I was getting nearly 10% better mpg, at only 5% increase in cost. I use Tesco 99.

No brainer.

nickv8

Original Poster:

1,442 posts

106 months

Monday 22nd March 2021
quotequote all
Orangecurry said:
Performance aside, I'll add that on a car with a dynamic/adaptive ECU, same as yours, with RON 99 I was getting nearly 10% better mpg, at only 5% increase in cost. I use Tesco 99.

No brainer.
According to https://www.rac.co.uk/drive/advice/fuel-watch/ Super unleaded is (on average) 9% more costly than normal. But I get your point.

gsewell

718 posts

306 months

Monday 22nd March 2021
quotequote all
Currently not overly bothered although I predominantly use Shell Vmax. From September, standard unleaded is due to go E10 which I am not so happy with as Ethanol absorbs water and if you don't use the car regularly, it could separate and cause real problems.

Koln-RS

4,090 posts

235 months

Monday 22nd March 2021
quotequote all
Clever marketing (Shell)?
Placebo effect?
Marginal, but barely detectable, benefits in normal use?

Probably all three.
But, like many, it gives me a nice warm feeling when I give the cashier my credit card.

gizlaroc

17,251 posts

247 months

Monday 22nd March 2021
quotequote all
You can use 95 ron on these cars, but it will retard the timing, giving you a drop in BHP and MPG.

It is a Porsche, they have been NA for years where people spend £10,000's on trying to squeeze another 10-20hp from them, and yet we have people putting in 95 ron which will loose that much from the official figures as you drive off the forecourt.


Forced induction cars tend to get hit harder, but NA engines that are designed to run on 98 will lose a fair amount of HP and MPG.

I rolling roaded my 335i touring a few years back as the difference between 95 and 98 was massive.
It dropped 30hp on 95 ron, which was roughly 10%. The MPG went from 30-31 down to 26-27 as well, so no cost savings to be had.

Tesco 99 was as good as any of the other super unleaded fuels and was often as cheap as the Shell 95.


Even our E350 estate was much nicer on 98 ron.
304hp on 98 and down to 281 I think it was on 95 ron, but the MPG was the biggest change, every time I reset the OBC it would end up back at just over 30mpg using 98, where as on 95 it would end up at 26.

Sainsburys fuel used to threw an EML on the Merc, and when scanned it would say the emissions post cat were too high and the suspected contaminated fuel or an unknown additive detected.



The problem is it can take a couple of tanks to get it running at full steam, but even 1/4 of a tank of 95 will set it back again.
Run it for a few tanks, better hp, better MPG and it burns much cleaner so far better for the car if you plan on keeping it as it gets a few years old.


No brainer.

nickv8

Original Poster:

1,442 posts

106 months

Monday 22nd March 2021
quotequote all
So... to confirm... diesel is an absolute no no too? wink

DJMC

3,584 posts

126 months

Monday 22nd March 2021
quotequote all
It was Tesco fuel which caused our 1yr old BMW to malfunction. Stopped using it and the issue never reoccurred.


gizlaroc

17,251 posts

247 months

Monday 22nd March 2021
quotequote all
DJMC said:
It was Tesco fuel which caused our 1yr old BMW to malfunction. Stopped using it and the issue never reoccurred.
What the Momentum 99 ron stuff?


DJMC

3,584 posts

126 months

Monday 22nd March 2021
quotequote all
Sorry, no. Diesel. The DPF became blocked. The BMW mobile technician asked "...have you been putting supermarket fuel in this?"

He then explained the double refining done by Shell, Texaco, and BP only and how all the others add sulphur to their fuels to boost the octane rating. Now some "experts" here will poo poo this but he had spent 30+ years working on many different brands and just knew we were "guilty" of using supermarket fuel.

Please do poo poo but also maybe add your own credentials in the motor industry allowing you to cast doubt on his assessment.

So I have transferred his perfect knowledge to the world of unleaded too. Their may be no link at all, but I'm not prepared to take the risk.

Prior to the BMW we had a DPF failure on an A3. Guess what fuel we used? And guess why it's cheaper?

gizlaroc

17,251 posts

247 months

Monday 22nd March 2021
quotequote all
I always add Archoil 6400D to my diesels. I replaced the gunked up manifold and EGR on my old E61 530d when I bought it with 60k on it, and when I moved it on with 118k on it I looked at the EGR and it had nothing more than a layer of dust you could wipe off with your finger.

Additives make a hell of a difference, and that is what you pay for in fuel, additives.

Mate of mine had no end of issues with his DPF constantly trying to regen, BMW wanted to put a new DPF in.
I got him to run Archoil and it went from trying to regen every tank to every every 3rd or 4th tank.


GT4P

5,798 posts

208 months

Tuesday 23rd March 2021
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Some supermarket fuels are brands ie Sainsburys is BP, morrisons use Shell and some Tesco have Essso

KPB1973

938 posts

122 months

Tuesday 23rd March 2021
quotequote all
DJMC said:
Sorry, no. Diesel. The DPF became blocked. The BMW mobile technician asked "...have you been putting supermarket fuel in this?"

He then explained the double refining done by Shell, Texaco, and BP only and how all the others add sulphur to their fuels to boost the octane rating. Now some "experts" here will poo poo this but he had spent 30+ years working on many different brands and just knew we were "guilty" of using supermarket fuel.

Please do poo poo but also maybe add your own credentials in the motor industry allowing you to cast doubt on his assessment.

So I have transferred his perfect knowledge to the world of unleaded too. Their may be no link at all, but I'm not prepared to take the risk.

Prior to the BMW we had a DPF failure on an A3. Guess what fuel we used? And guess why it's cheaper?
I have 10 years plus working in the breakdown industry, with particular focus on manufacturer-supplied policies.

Rule no.1 of delivering roadside assistance is to never, ever, criticise the brand. That includes confirming any well-known issues with a particular component (minor or major). Even for the likes of the AA or RAC, the patrols can be disciplined for concurring or implying with the owner that they've spent a lot of money on a car that is likely to break down. I know this from direct experience.

So in your case, I would suggest that the BMW mechanic is playing to his employer's rulebook and blaming a third party (the fuel) rather than you the owner (for your pattern of usage) or the car (for having a component failure or not regen-ing the DPF).

If you extrapolate your 100%-failure rate across two brands the wider population, then you'd be looking at the vast majority of VAG and BMW diesels experiencing a DPF-related issue.

Having owned 3 x diesel BMWs (640d GC, 125d F20 and 530d F10) and a similar number of VAG diesel cars (Eos 2.0tdi, A3 2.0TDi, Ateca 1.6TDi) in the last 6 years, I can confirm absolutely zero DPF issues across approx 160k miles.

All were run on supermarket fuels and used across a variety of journey types.

I think, sadly, you've just been very unlucky - especially if you do regular longer journeys where the DPF has opportunity to regen.