I have a mk4 2.0litre. Is there any benefit to using super plus unleaded 97 ron. I currently use standard 95 ron but I’ve noticed that some petrol stations are doing a 99 ron. It says on the filler cap minimum 95. I’m not bothered about getting more power. I just want to use what’s best for the engine. Please help. Thanks in advance for any help.
Any quality fuel
in other words stay away from supermarket petrol
As for rating the more octane fuel has the better it burns more efficiently and more power but it also costs a little more
if your not running high powered engines i wouldnt worry too much octane wise as long as its up to min spec of car
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You have opened up an old can of worms here.
I have used supermarket fuels for over 50 years in both petrol and diesel cars and never had any issues. I ran a fleet of 40 cars at work and never had any issues with any of them either.
If you can afford the more expensive fuel then use it by all means.
If you are going to ‘track’ you car then put some good stuff in for the day.
Hang on to your hat for the deluge of opinions that may follow.
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I’ve spent most of the last 10 years or so hanging about the Mitsubishi Evo scene where it’s almost regarded as a cardinal sin to use anything other than Shell V Power! That’s partly because many Evos will have been re-mapped on that particular fuel and so it would be foolhardy to use anything else, but it’s also the fuel of choice in general. That said, most modern cars have ecus that will actively look for det (detonation) and will then adjust ignition timing etc to nip it in the bud, and so running a lower grade fuel won’t damage the engine, although performance might be down slightly.
If I had a mk4 I would, out of habit more than science, go for V Power every time, but the only real difference between using that and regular, including supermarket, 95 fuel might be marginally better fuel consumption.
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I have 1.5l and 2.0l ND/Mk.4’s and I’ve used Tesco fuels and Shell fuels and I really can’t tell the difference, but every so often I make a point of filling up with Shell V Power because I’ve been led to believe that the additives in it help clean the engine. I have no way of knowing whether that is a fact or not, but it doesn’t hurt to use it once in a while just in case.
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Tesco Momentum in my ND 2.0, performance very satisfactory for me.
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Yes, you can see benefits with 98 RON in particular with the higher specification/compression engines, (Their is a reason).
Remap can achieve “slightly” better results with 98 RON.
In my opinion the majority will see no real difference in the the normal day to day driving.
95 and 98 Ron fuels ALL have to meet the UK/European specifications whether supplied by the the main brands or supermarkets.
I’ve used both supermarket diesel and unleaded for donkeys years with no problems.
Actually gains by money in my pocket! 
In my opinion you would be very hard pushed to find a supermarket supplying rubbish fuel. It would just not be worth the while if they got caught out?
Never seen any reports of supermarket fuel under performing or damaging engine’s (apart from accidental water ingress).
Any takers with a difference of opinion with reports stating otherwise?
I support and agree with Mad_Malc’s view to be honest.
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Just looked at Shell V Power which is 99 RON.
"THEY claim " increased performance, lubrication and cleaning.
Apparently, it works for the cars that are actually tuned for it, (as previous comments).
Perhaps a tuner can give us a clear definitive answer?
It would be interesting to know if Mk.4s with their more modern ECUs can make any more power or return any more mpg on high octane petrol or different brands. I know from my first Mk.1 that petrol brand and octane made not a scrap of difference to mpg in that model. I had the same long-ish commute for many years and would experiment with at least 4 full tanks of one fuel before switching to another. No difference. I will say that after I supercharged that car it felt subjectively smoother on Shell Optimax, later V-Power, or Tesco 99, later Momentum, than on any other high octane fuels I tried. Also I uprated the fuel pump as part of the upgrade and found the inside of the petrol tank was as clean as a new pin, despite years of mostly supermarket petrol. None of that “sediment at the bottom of the tank” fearmongering.
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Hi team
I have a 2 litre ND2 and always use Shell V power,i feel it is a better fuel and protects the car engine more and poss more performance,also i am convinced that i get more M.P.G that pays the price difference,on a holiday of 2000 miles round the pyranees touring last year,the overall average according to car readout was just over 50 M.P.G,on many other occasions it has returned over 48 M.P.G.
Also as i think total confirmation of more M.P.G with Shell V.Power until recently i had a Honda C.R.V diesel that i pulled a caravan with,one very reg journey was to a particular sight in norfolk,driving there with full tank of V.Power diesel,my return journey was with supermarket diesel as that is what was available where i was in norfolk,identical route both ways taking care to drive very steady to do true comparison,every time the fuel consumption with V power diesel was always better with at least a 4 M.P.G improvement with V.Power,also the car seemed to run slightly smoother,so i am convinced by useing V.Power not only is it slightly better for my car,but always def feel that i save the price difference at least.
All best Simon
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I agree with you on the occasional use of Shell V Power. Mine failed the MoT on emissions in March before the lock-down, so I spent a week using Shell V Power, in addition to a bottle of Cataclean, and the engine sailed through the re-test. I was not too bothered if it was just the one product, or using a combination of both, but the fact it worked was OK with me.
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I have used nothing but BP Ultimate from day one. I cannot say if it’s better, but thought I want to keep it looking good so why not make it run good as well.
I did have it remapped and the fitter asked which fuel I used and tuned it that fuel.
I guess it’s really down to what you’re happy with burning in your engine.
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Just love these debates.
My understanding is that ALL the fuels have the same cleaning additives/detergents to keep parts clean and it’s an industry standard.
Just been doing a bit of mathematics for V Power V Standard 95 RON.
Lets’ “Say” you get 2 miles per gallon extra……….(as posted).
With an average difference of say 5 pence per litre, (could be more or less just an example) but generally 10% more?
Not too sure what the actual price is at present as not been out.
£1.20 x 4.5 = £5.40 a gallon for V Power. Divided by 50 mpg = 0.108 pence per mile.
£1.15 x 4.5 = £5.17 a gallon standard 95 RON. Divide by 48 mpg = 0.107 pence per mile.
So according to the mathematics you end up paying “more for V Power” in the long run per mile.
Which in my opinion negates the use of V Power for extra MPG.
Just thought I would throw that one in!
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Good point Scarletpimpernel, but more so because the difference around Doncaster is closer to £0.12p/litre, so the differential is going to be greater. That is why I will only indulge for the occasional use, as the difference is too great for me to want to use on a more regular basis. At £0.05/litre though, I reckon I probably would use it more frequently.
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Gosh is it that much!
I know my friends from Yorkshire certainly wouldn’t bother then.
Agreed, I think I would use it too and have the car remapped for the use of, but for me its just not cost effective with everything thrown in.
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You have to think that no supermarkets have their own refineries just like they don’t make their own brand Ketchup.
Fuel prices are somewhat of an anomaly at the moment but stuff like V power is typically 10 to 30p per litre more than standard. At “normal” prices and at the lower end it is 7.5% more which means 35mpg would need to become 37.5mpg in man maths figures.The bigger that price difference between standard then the mpg needs to rise to keep up. The issue is, the “test figures” that are quoted are performed on test rigs and not normal driving with a analogue human foot in control.
The benefits on a power front, I am sure most know, come as the engines need to be retarded less and will make more peak power. Many people though will never see this benefit as it involves the right foot and the needle being north of 5K. Economy wise, most modern engines will seek to lean the mixture as much as possible when “cruising” and a higher octane will allow this to happen a bit more. However it is the more modern engines that do this most. I had a 2003 MK2 dynoed once and it was said then that the ECU was only looking to perform any sort of economy function to around the 100kmh (62) benchmark after which it ran rich.
Modified maps and forced induction naturally are usually tending to optimise and increase things and so higher octane it far more beneficial. You can get 110 Octane from the pumps at Silverstone if you are feeling adventurous, take your Gold Card with you though.
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I vividly remember one of my friends at Uni putting Cleveland Discol 101 octane in his BSA Rocket Gold Star, and holing a piston while still on the first tankful! The engine seized and threw him off and the unpiloted bike then also bent its forks when it dived into a pothole to practice somersaults. It was most spectacular to watch. All this within a week of him buying it.
But then he had also been playing with the ignition timing to “Make the best of the octane.”
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Bet you couldn’t stop laughing once you picked him up and found out he was alright! 
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Yes, this little chestnut crops up on odd occasions, and every member will have his (or her) own opinions about it - but you did ask ! OK, so here’s my five-pennyworth.
Our first MX-5 was a brand new (in 2011) 2.0L Powershift Coupe. It was my wife’s company car, and as she was driving it back-and-forth to Bristol (25 miles each way) every day, she put bog-standard, minimum requirement 95 octane in it. And I must admit, the car went very well, and we were both pleased with the performance and fuel economy.
When the car had to be returned at the end of the lease-hire period, we missed the ability to go topless so much,that we bought another 5 as a second car / plaything. We didn’t like the body styling of the ND (which had just been released), so bought a low-mileage, well looked after 2008 2.0L coupe again, but a manual one this time.
Immediately, I noticed it running rather unevenly on the 95 octane stuff, so tried premium instead - an absolute transformation, so we have used the expensive stuff ever since.
I’ve no idea why one car should be fine on cheap fuel, and another not happy about it at all - just life I guess. But anyway, we have found that the 2008 car which we have now, gives better fuel economy than the other one did - about 4 or 5 mpg better.
In the end of course, you have to decide what fuel you want to use, considering your own circumstances.
Personally, we always use premium stuff from our local Sainsbury’s. We tried Shell V-Power for a while, but didn’t feel it was any better than the supermarket stuff.
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I started using BP Ultimate to counteract some rubbish unbranded fuel that I had to put in when out in the sticks and nothing else available. Previous to that I had been using the regular 95 RON, but found Ultimate (97 RON) to be so much better that I stuck with it. I don’t know what it does for max power, but definitely feels smoother and torquier at the bottom end. I pay 10p/l more for Ultimate, but V Power was 18p extra last time I used it. I suspect that I get somewhat better mpg, but don’t have any back-to-back data to prove it and I figure that my with relatively low mileage any extra cost is irrelevant.
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