Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be?

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Fri 23 Feb 2018 17:16
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - John F

I occasionally treat the uberwagen to a tankful of 'premium' fuel in the probably mistaken belief that it will spring clean the injectors and 'do the engine good'. (I have previously proved that the percentage better fuel consumption is considerably less than the percentage increase in price from 'regular' RON 95 fuel). However, the small print on the Sainsbury's nozzle says RON 97, not the 98 mentioned in every owner's handbook I have seen - admittedly not many. Shouldn't 'premium fuel' be at least 98? Are we being diddled?

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Fri 23 Feb 2018 17:33
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - skidpan

95 RON petrol is Premium Unleaded.

The 97/98 RON stuff is Super Unleaded.

Don't think anywhere sells Regular in the UK, from memory its 92 RON.

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Fri 23 Feb 2018 18:15
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - Big John

Tesco's higher octane petrol (Greenenergy) is 99RON

Filled up my Superb with the stuff yesterday

Edited by Big John on 23/02/2018 at 18:16

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Fri 23 Feb 2018 18:21
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - Metropolis.

Don't get the supermarket petrol, stick to BP or Shell premium. The shell stuff is 99 if i recall correctly. I only use V power diesel.

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Fri 23 Feb 2018 18:40
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - Glaikit Wee Scunner {P}

I filled up on the premium Esso stuff the other day, 97RON. My Skoda Octavia 1.4Tsi should adapt to this and I "may" experience increased power and mpg. I also hope that the 97RON will cause better cleaning of the engine than the 95RON. But hey, we live near Hope(adjacent to Castleton , Derbyshire)

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Sat 24 Feb 2018 09:43
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - skidpan

Ran my 1.4 TSi Leon for 4 years on supermarket 95 RON and have been running the Superb 1.4 TSi for a year now on 95 RON supermarket. Both are absolutely fine on it so will not be wasting a single penny on something that may or may not be of benefit. The book says to use 95 RON in the car and that is exactly what I will do.

For the record I have just looked inside the fuel flap and it clearly says 95 RON. I have no doubt that using 98 RON will do no harm other than to your wallet.

Edited by skidpan on 24/02/2018 at 10:23

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Sat 24 Feb 2018 11:24
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - nellyjak

I filled up on the premium Esso stuff the other day, 97RON. My Skoda Octavia 1.4Tsi should adapt to this and I "may" experience increased power and mpg. I also hope that the 97RON will cause better cleaning of the engine than the 95RON. But hey, we live near Hope(adjacent to Castleton , Derbyshire)

You "may"..then again you "may not"...personally I wouldn't waste my money.

95 RON is premium fuel and fine for the vast majority of cars...and is often referred to as "standard" or "regular" only because it's what the majority use.!

..and I know Hope well having been born in the Peak district (near Matlock)

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Sat 24 Feb 2018 11:48
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - Metropolis.
Got a lexus is250 in the family, always maintained by lexus.
It was running a little rough (still smoother than most other cars mind!)
Took it to lexus and were told to run it exclusively on premium unleaded. Problem cured!
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Sat 24 Feb 2018 13:41
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - nellyjak
Got a lexus is250 in the family, always maintained by lexus. It was running a little rough (still smoother than most other cars mind!) Took it to lexus and were told to run it exclusively on premium unleaded. Problem cured!

So what were you running on before.?????..and what is their interpretation of "premium".?

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Sat 24 Feb 2018 13:46
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - Metropolis.
They said don’t use the regular petrol. It was being run on the regular fuel, mainly from shell garages. By ‘premium’ I think we all know this means the more expensive of the two, unless you’re making a broader point?
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Sat 24 Feb 2018 16:16
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - nellyjak
They said don’t use the regular petrol. It was being run on the regular fuel, mainly from shell garages. By ‘premium’ I think we all know this means the more expensive of the two, unless you’re making a broader point?

What do they mean by "regular" fuel.?...95 RON IS premium fuel. (only termed as regular because it's the one we all mainly use)..unless you have a high performance car and/or one that demands a higher octane, then you are just chucking money away IMO.

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Sat 24 Feb 2018 16:43
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - skidpan
They said don’t use the regular petrol. It was being run on the regular fuel, mainly from shell garages. By ‘premium’ I think we all know this means the more expensive of the two, unless you’re making a broader point?

What do they mean by "regular" fuel.?...95 RON IS premium fuel. (only termed as regular because it's the one we all mainly use)..unless you have a high performance car and/or one that demands a higher octane, then you are just chucking money away IMO.

Totally agree. if you ahve a tuned Scooby, Ferrari, Porche etc I can see the benefit especially if the engine has been mapped for it but for ordinary motors its just wasted.

My Caterham has been mapped for 95 RON simply because it mean I can buy it anywhere without searching. Perhaps I might gain a couple of BHP if it was remapped but at what cost and benefit.

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Sat 24 Feb 2018 18:54
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - focussed

If you want clean your injectors, run the tank down to 1/4 full and stick a bottle of injector cleaner in the tank. Run that until the reserve light comes on and then fill with ordinary 95 unleaded.

I have tried running one of my motorcycles on 98 super, absolutely no difference in performance or economy, so now everything petrol engined in the fleet gets 95 UL.

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Sat 24 Feb 2018 20:38
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - KJP 123

In answer to the OP.

I think that it is the extra detergents that Shell claim to put in their top fuel that is more important than the octane rating so supermarket premium will probably make no difference.. Also the occasional tank full would probably not be enough.

Cars that are designed to run on 95 get no performance or economy benefit from running on 98. Cars designed to run on 98 should benefit slightly but not to the same extent as the the extra cost involved.

It’s odd why premium in UK only has to be 97. In France, and I presume much of the rest of the EU, it is all 98. That is why handbooks say 98.

"Shouldn't 'premium fuel' be at least 98? Are we being diddled? " Yes and yes.

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Sun 25 Feb 2018 10:04
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - skidpan

I think that it is the extra detergents that Shell claim to put in their top fuel that is more important than the octane rating

And there is the problem, its just a claim. Occationally they produce nice colour photo's of dismantled engines showing how much cleaner one is than the other but there is no proof that the engines involved had actually been used for 100,000 miles on 2 different fuels.

The most miles I have ever done in a car was 113,000 in a Golf. Had it form new, always used supermarket 95 RON and did quite a bit of towing during the summer months (race car on trailer). At 7 years old the emmisions were still factory spec at the MOT and when a few days later I was pulled for a DVLA roadside check they were stunned that it was so low on a car with that mileage.

So no 98 RON for me, why would I spend more when 95 RON does the job perfectly well.

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Sun 25 Feb 2018 13:09
Petrol engined cars which prefer RON 98 fuel - Is 'premium fuel' as premium as it used to be? - John F

In answer to the OP.....

........"Shouldn't 'premium fuel' be at least 98? Are we being diddled? " Yes and yes.

Thank you KJP for probably the best answer yet on this thread. I really should have searched on the forum before I posted as I have just discovered this was discussed nearly 13yrs ago!

www.honestjohn.co.uk/forum/post/index.htm?t=32849

Still, no harm done to revisit it.

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Real MPG enables you to register the fuel economy you are actually getting against your make and model of car, its engine and type of transmission.

Every time you enter an average consumption figure against your car, the overall average automatically adjusts to reflect it.

Real MPG