vRS TSi Fuel - Any difference?

[Alex-W]

So, is there any factual evidence regarding the performance of a car with a TSi engine on different grades of fuel?

 

The vRS can obviously run on 95ron upwards, but what's the benefit?

 

I have tried  95 and 97 RON and hadn't noticed any difference in economy or power day to day.

 

However....

About 2 months ago I had to do a ~300 mile round trip in a day on pretty much all motorway.  Usual traffic during rush hour, but once going, steady cruise control most of the way.  I got about 46mpg over the day.

I was using 97ron.

 

I had to do another similar journey this week, motorway and cruise control.

However I was using 95ron.

It didn't want to go over 42mpg average.

 

Both similar temperature days, around 8degC.

 

I'm starting to wonder if there is a mpg benefit to the higher octane fuel.

 

When I started using it last year, I couldn't see an increase in economy day to day, however it was around October time and the weather got cooler so that would hugely affect it anyway.  I've gone from 36mpg to 30mpg on my commute generally.

 

The problem is due to variation in so many other factors it's hard to get definitive answer.

 

Ultimately, it's 124p per litre for 95 and 130 for 97.  That's 5% more expensive...  Do you really get 5% more miles?  it's kinda looking like on longer runs you get up to 10%.  And is 99 a worthwhile increase from 97 considering its more expensive again.

 

Just to clarify...

I'm well aware that the price difference is only ~£3 over a tank and tbh it's not a huge deal either way, however it if interest I'd like to know if there's a quantifiable advantage.

I'm also well aware that my two long drives are not scientific and I'd need to do it over a much longer time period to get reliable data.

Edited 17 January, 2020 by Alex-W

[Ootohere]

That might be Shell V-Power that is more expensive again.

Shell Fuelsave 95 ron can be more expensive than Tesco 99 or Sainsbury's 97.

 

Maybe try Tesco Momentum 99 (99 ron minimum) because the difference is 5 pence more a litre from Tesco 95 ron.

Sainsbury's Super Unleaded 97 is 5 pence a litre more than their 95 ron where i pass.

 

Mid to Late October you started getting Winter Formulation petrol Unleaded or Super unleaded.

It can be lovely stuff, maybe blended local to you maybe it came right in from Continental Europe and 99 ron min could be 100 Ron and 100 +

Stock Fuel for Royal Dutch Shell & Greenergy that produces and supplies Momentum 99 & other fuels including Esso 97 Super Unleaded comes into shared storage facilities on the same tankers.

 

If you feel no smoother running or see no more range from a tank then just don't buy again.

http://volkswagen.co.uk/need-help/need-help-faqs/owners/Fuel

 

Edited 17 January, 2020 by Roottootemblowinootsoot

[Alex-W]

I generally end up buying Sainsbury's 97 as I was told a long time ago it's BP fuel, good quality, decent price and tbh it's just convenient for me as it's on my way to and from work.  

 

What do they do to the fuel in the winter?

 

 

[Ootohere]

A less Hygroscopic formulation.   Maybe Google it. 

[ChoonDoode]

You've seen there one of the differences; the gain in MPG. Given the higher RON, the timing is being retarded to make use of the fuel. If you're just motorway cruising predominantly, I wouldn't bother putting 'premium' in. If you're going out for the day, on the back roads and looking to have a bit of fun, then potentially you 'may' notice the 'extra' power from the fuel. The only problem with swapping to and from basic to premium is you have to run it down to fumes and then fill up. Otherwise for a good while, you'll still be running on basic before eventually the premium starts to get into the lines and the car can make the use of it.

 

I'm a believer of using the best fuel which I can afford and in my case it's V Power (diesel for the car and petrol for the bike). The main difference which I can see in the car is the DPF ash content. Working it out at the moment, it'll take til around 250k miles before the ash level hits 80g. Now, I do a lot of motorway miles, but I still need to do slower town driving. I certainly do think the 'cleaners' in it are beneficial.

 

The petrol V Power in my bike makes the difference to how it runs. It is recommended to be run on RON 98+, but you can 'getaway' with 95. I was forced to use it a few times and you can tell the difference. BUT, that's because it's in-effect in a sort of limp mode. It can use the 95, but it's designed to run 98+. The VRS does have the ability to adjust timing to make use of premium fuel. Fifth gear did a test with a Mk7 golf gti and the V Power produced 5hp more than ASDA cheapo. The price difference was 9p/lt at the time. It's more a case of whether you're willing to pay the extra.

[Gerrycan]

It is a topic covered many times in the forum and my exexperiencthere is no noticeable difference with my 1.4tsi so I stick to local (Aussie) 95.

However the vRS is probably capable of adjusting its 'tune' to accommodate higher ron fuel and improvement is reckoned to be about 1% per ron rating. Couple that with Euro 95 ron has at least 5%  ethanol content and the higher ron is likely to have no ethanol so there is another 1% or so extra calories per litre in the more expensive fuel.

All the consumption and emission tests are conducted with 95 ron so you would think that manufacturers would have optimised the engines for it.

I might try some local 98 ron for a few tanks again just to see.

 

Edited 18 January, 2020 by Gerrycan

[Ootohere]

All test are to be carried out on 95 octane is because that is what the WLTP / RDE & now RDE2 requires. 

It in no way means that an engine can not perform better than the WLTP / RDE / REDE2.

When Car Reviewers / Journalists collect a media car or a car at launch and drive it and do a review unless they go fuel it they have no idea what octane of fuel the Media team have in.

When Car Magazines do their annual Car of the Year features they have their Filling Station stops arranged and where there might be no Super Unleaded available have Fuel Supplies arranged.

 

The question needing asked is.

 

Are 1.4TSI for Australia / New Zealand, China and non European Countries running the same Software / Engine Management as European 1.4TSI's.

Reason being that they can benefit for higher octane fuels.

There are different Maps / Engine Managements for South Africa a North America. Different Max PS & Nm Torque outputs.

 

VW are the ones that call World Wide Recalls and exclude Europe as being in the World.

Reason being they say there are Environmental and climatic differences.

 

@tunedude  Is Shell V-Power Nitro + (99) actually better than Tesco Momentum 99 just because Shell Stations charge more?

Look back at both Fifth Gear vids of fuel testing & the later one.

That was when BP Super was 97 and Shell V-Power was 98 octane minimum.

In the UK BP is now 97 ron and Shell V-Poer Nitro + is 99 ron .

 

Price differences today is very different from 2012 between 

Shell V-Power Nitro + 99 & Shell Fuel Save 95

Gulf Super Unleaded 97& Gulf 95

Esso Super Unleaded 97 & Esso 95

BP Super Unleaded 97 & BP 95

Sainsbury Super 97 & Sainsbury 95

Costco Super 97 & Sainsbury 95

Tesco Momentum 99 99 ron and Tesco unleaded 95.

 

 

 

 

 

 

Edited 18 January, 2020 by Roottootemblowinootsoot

[Ootohere]

Tesco at least had their 95 and 99 ron fuel tested alongside others for emissions and published the results. 

Various vehicles used in the testing.

 Greenergy produce and supply fuels for others like Esso in the UK.

Tesco no longer have these  reports readily available. so i saved them.

 

Never seen the other fuel producers or manufacturers show their test results though.

388380a097b04fe693a8c27db8bb4974 (1).pdf 6ca06d648b9541e78fa838fece4a1a23 (1) (3).pdf

 

 

Edited 18 January, 2020 by Roottootemblowinootsoot

[silver1011]

Comparing two journey's isn't conclusive.

 

Something as simple as a tailwind vs. headwind can easily result in a 4mpg difference.

 

You need to run one fuel for a few months, then the other.

 

Are the fuel economy figures you quoted a manual calculation, or from the onboard computer?

 

Manual calculations after each refill is more accurate.

[ChoonDoode]

4 hours ago, Roottootemblowinootsoot said:

 

@tunedude  Is Shell V-Power Nitro + (99) actually better than Tesco Momentum 99 just because Shell Stations charge more?

 

 

No, I was merely comparing Shell because that's the petrol station up the road from my house.

 

and that top video was the one I found

Edited 18 January, 2020 by tunedude

[Ads230]

My approach as been "IF modified (mapped), THEN use higher RON fuel".

 

I typically use Shell V-Power, as I do like the occasional free coffee and also now BP dropped Nectar, I can't trade fuelling for food anymore 😪

 

Noticed a major difference with the addition of the Stage 1(.5) map on my VRS in that I got +4 mpg average on ALL journeys, and generally get higher mileage between refuelling. I've had tangibly increased range with higher RON fuel (if not 'noticeable' power increases), but I want the 'assurance' of higher quality fuel running through a mapped engine. Worth the money IMHO.

[MarkyG82]

12 minutes ago, Ads230 said:

 but I want the 'assurance' of higher quality fuel running through a mapped engine. Worth the money IMHO.

 

This every time whether petrol or diesel.  We may be taking ownership of my dads CRV oil burner which at 160ps from a 1.6 as standard I think will benefit from regular posh fuel.  If only to keep the DPF in check.

[gregoir]

I have used 3 full tanks of Tesco Momentum. No improvement in the mpg, but there is a strong increase in the perceived torque at 2000rpm. Like the surge in delivery of my old turbo diesel. The tsi does have variable inlet and exhaust cam timings (via hydraulic servos) to take advantage of higher octane fuels. There is an inbuilt knock sensor I believe. SWMBO rarely drives my car and she basically said WOW pulling away from a roundabout. 

I imagine the VRS tsi is the same. 

[Warrior193]

Averaged over more than 8 tank fills, I am seeing an increase of around 2MPG (both on fuel computer and actual calculation) when using Tesco 99 Momentum - most mileage is on 18 mile (return) commute to work on local roads,  trip to work very early in morning, return in normal! South-West London traffic. Translates to around 430-440 miles per tank - refuelling at 45-48 litres used. Usually struggled to get 400 miles to a tank when using 95RON unleaded with the same usage. A jerry can tends to feel pretty heavy after more than a mile or two!

[matrix2020]

I ran my Golf R (310) on a variety of fuels but mostly Tesco 99, TBH, I found virtually no difference in any of them at all. As previous have said wind, driving style, temperature all made far more difference so any fuel differences were not noticeable. I ended up using standard fuel (easier to get!) far more at the end because it made such little difference.

[Lingnoi]

I've been running my 1.4TSi Octy on Tesco Momentum 99 as an experiment for a few weeks now and unfortunately there aren't any Tesco garages near me so I diluted it with Costco RON97. I have to say the car feels more "spritely" since I switched to higher octane fuel, smoother acceleration and greater torque but it's not a massive difference. For the moment I'll continue running on the more expensive juice. I suspect I'll notice the difference more when I switch back to boggo 95RON fuel.

[Gerrycan]

I'll concede  that a chipped car will run better on the fuel it has been optimised for during tuning (preferably) on a rolling road.

The question I have is that  tuning occurs under the existing set of conditions (temperature/humidity/barometric pressure/altitude) so what potentially happens outside of those conditions?

A manufacturer has to produce a lower more flexible tune engine that will be run well in a variety of conditions and also with different types of summer/winter fuel.

 

In answer to a question posed above about the state of 'tune' of VW vehicles delivered to other markets then the answer is yes they can be a 'bit' different. 

The high output VW/Audi/Porsche vehicles issued to the Australian market usually produce a few less kW ostensibly because of our 'hot' climate but interestingly those to the Middle East are not downgraded so it is more probably due to issues with our high sulphur content fuels than climate.

The Australian emissions regulations are still locked at Euro 5 levels so the Octavia still has the 1.4tsi and other models where the 1.5tsi are installed then there is no GPF fitted.

Interestingly Peugeot use a different GPF system and are now selling them fitted here on their latest petrol cars, claiming our high sulphur fuels are not a problem.

 

Seat-of-pants opinions of the relative merits of using low/high octane fuels would have greater credibility if the driver did not know what fuel was actually put in the tank. There are very good reasons why only double-blind testing of medications are accepted as scientifically acceptable.

Sorry that is the sceptic in me speaking and should not deter anyone from putting the fuel in they believe works best for their car, driving feel and wallet.

Edited 23 January, 2020 by Gerrycan

[shyVRS245]

Well as some of you know I like tinkering with my cars and can give some figures on 2 Turbo petrol and 1 Turbo diesel cars I have owned, what fuel I used and the standard power and torque plus remapped figures. My attitude has always been if you can't afford the more expensive fuel don't bother. Similarly don't remap your car if you are not prepared to put the highest octane fuel in it.

First the diesel a 2013 Mk3 Octavia 2.0TDi SE which Skoda claimed produced 148bhp and 236lb/ft of torque. On AmD rolling road it actually produced 147bhp and 246lb/ft as standard on BP Ultimate diesel.

Stage 1 remap increased power to 186bhp and torque to 317lb/ft. Top speed increased from 135mph to 150mph. On the journey to Essex (136 miles each way) the maxidot read 71mpg average and return journey after remap maxidot read 70mpg.

Second vehicle SEAT Leon Cupra in 2004 with the Audi TT engine 1.8T petrol which was claimed to produce 177bhp and 173lb/ft of torque. Running on Shell V-Power as standard it produced 190bhp and 193lb/ft of torque.

Stage 1 remap increased power to 230bhp and torque to 230lb/ft. Top speed increased from 142mph to 148mph. The 55 litre tank (12 gallons) gave a maximum range on a run of 360 miles or 30mpg.

Third vehicle Skoda Octavia Mk3 RS245 which has been well documented on here Skoda claimed 242bhp and 370nm of torque. Bought new in 2017 like the other vehicles above and all remapped at between 6,000-9,000 miles. Running Shell V-Power Nitro (99octane) it actually produced 249bhp (252PS) and 400nm as standard. Max speed was 160mph.

Stage 1 remap increased power to 302bhp and torque to 467nm (standard 273lb/ft and now 345lb/ft) with a max speed of 165mph. With uprated intercooler, cone air filter and 3" stainless steel exhaust plus 3" downpipe with sports cat it produced 336bhp and 517nm of torque (380lb/ft) with a Stage 2 remap at 14,500 miles. Max speed was now a heady 177mph and when I sold it with 29,000 miles on the clock it had averaged (actual calculated based upon fuel purchased) 40.3mpg when Skoda claim a 6 speed manual car like mine had a combined figure of 42.8mpg. Typically it would do 440 miles per 50 litre tank or 11 gallons but on a long run it managed 526 miles at an actual average 47.8mpg. These are all facts and not my gut feeling so you pay your money and can see the benefits with turbocharged engines both in performance and fuel economy.

[mobil531]

I use 98 not for any performance or fuel consumption issues (Doubtful anyway) but just because I hope it is of a high quality. Makes me feel good anyway.

Regards

Roger

[Gerrycan]

1 hour ago, shyVRS245 said:

Well as some of you know I like tinkering with my cars and can give some figures on 2 Turbo petrol and 1 Turbo diesel cars I have owned, what fuel I used and the standard power and torque plus remapped figures. My attitude has always been if you can't afford the more expensive fuel don't bother. Similarly don't remap your car if you are not prepared to put the highest octane fuel in it.

 

 These are all facts and not my gut feeling so you pay your money and can see the benefits with turbocharged engines both in performance and fuel economy.

The figures are interesting in themselves and I agree with you about higher octanes for tuned turbo vehicles but do not really answer the OP's original question about the relative merits of more expensive fuel for his standard vRS.

There have any number of 'independent' tests published and also available for viewing online on the efficacy of 'better' (more expensive) fuels for standard vehicles, but most are either a 'marketing promotion' or lacking in scientific rigour.

One of the more interesting Briskoda threads in the Fabia mk3 section had contributions from a now retired automotive engineer involved into research on small trbo engines that concluded that the higher octanes may produce lower power than standard fuel. It incidentally also noted consumption improvements over the run-in process, not huge as some have reported but worthwhile non the less. Again not my experience but I cannot criticise their methodology and conducted on a far more rigorous scientific basis than I could ever aspire to.

 

I tried a few tanks of local 98 octane fairly early in the Mk3 ownership because the local Skoda tech recommended I try it to fix a \n occasional cold start issue where the engine was jerky for the first few hundred metres.

When I was confident the whole tank was 98 Octane I was able to duplicate my reference conditions (20 deg temps, no wind, 110kph gps speed on same flat road, no other  traffic  with cruise control) and the instant figure was an identical 5.7L/100 (49mpg) to my original 95 Octane results. If it had dropped to even 5.6L/100 I could find some justification in permanently changing despite the extra cost. Needless to say it did not fix my original occasional cold start jerkiness either which exists to this day.

[MarkyG82]

I'd also like to add another thought.  Sale of unworthy goods (particularly one so prevalent as consumer vehicle fuel) would likely be scrutinised to a point where if there were no real changes (benefits?) to using a different fuel then it would have been called out by trading standards, or some such other body, and pulled from the shelves.

 

I'm not saying this is the case as I cant think of another product off the top of my head this has happened to but you do find that most dodgy products are sold in less controlled spaces - ebay, aliexpress, amazon, etc.

[Gerrycan]

If you look closely at any advertising for any product you will notice use of the words 'may', 'might', 'could', 'potentially' and the simple 'up to'.

Makes it difficult to make a legal case against them based on their advertising 'claims'.

However I think it is fair to say there will be some (mostly performance)  engines for which there is benefit from using a higher octane fuel.

The manual of my 2003 Toyota Echo 1.3L naturally aspirated engine says higher octaines than our locally available 91 Ron can be used but there will be no benefit. 186k km on the clock suggests they were right

Edited 23 January, 2020 by Gerrycan

[Ecomatt]

7 hours ago, Gerrycan said:

The figures are interesting in themselves and I agree with you about higher octanes for tuned turbo vehicles but do not really answer the OP's original question about the relative merits of more expensive fuel for his standard vRS.

There have any number of 'independent' tests published and also available for viewing online on the efficacy of 'better' (more expensive) fuels for standard vehicles, but most are either a 'marketing promotion' or lacking in scientific rigour.

One of the more interesting Briskoda threads in the Fabia mk3 section had contributions from a now retired automotive engineer involved into research on small trbo engines that concluded that the higher octanes may produce lower power than standard fuel. It incidentally also noted consumption improvements over the run-in process, not huge as some have reported but worthwhile non the less. Again not my experience but I cannot criticise their methodology and conducted on a far more rigorous scientific basis than I could ever aspire to.

 

I tried a few tanks of local 98 octane fairly early in the Mk3 ownership because the local Skoda tech recommended I try it to fix a \n occasional cold start issue where the engine was jerky for the first few hundred metres.

When I was confident the whole tank was 98 Octane I was able to duplicate my reference conditions (20 deg temps, no wind, 110kph gps speed on same flat road, no other  traffic  with cruise control) and the instant figure was an identical 5.7L/100 (49mpg) to my original 95 Octane results. If it had dropped to even 5.6L/100 I could find some justification in permanently changing despite the extra cost. Needless to say it did not fix my original occasional cold start jerkiness either which exists to this day.

I bet any money the jerkiness is the spark plugs. Id fit one stage cooler plugs and see how it goes. 

[Bugginbob]

I've finished running my VRS 245 Challenge in now and done three tanks on standard Tesco unleaded driving "normally" since then. Not ideal timing weather wise with cold and ice but have not had better than 29mpg (measured) on any of those three tanks. Although I was barely getting over 30mpg when I was running it in either. Filled up with Tesco99 today and will run it for a month on that (approx 1200 miles) and see if it makes any difference MPG or performance wise. If not a noticeable difference I wont bother as not particularly bothered by the MPG. Although it would be nice to get more than 300 miles between fill ups I suppose.

[Gerrycan]

On 24/01/2020 at 00:48, Ecomatt said:

I bet any money the jerkiness is the spark plugs. Id fit one stage cooler plugs and see how it goes. 

 

My car has not had any special chipping and just runs recommended spark plugs. The car is now getting on for 6 years old and I had the spark plugs replaced only last year with standard at about 50k km and asked for the ones taken out to be returned to me to get some idea of condition, carbon build up and any other obvious issues.

I was surprised by the excellent condition they were in, they looked as though they could have done another 50k km.

 

The engine starts first time every time before even half a crank and then idles perfectly. It is only when I drive the 50metres to the road in first gear that I am aware of how jerky it is. From there I can accelerate the engine upto the 40kph limit whee the jerkiness is less obvious and disappears after a few hundred metres.

The odd thing is occasionally (and for no apparent reason) the first start of the day jerkiness is not apparent, the car drives smoothly and the average consumption at 1.2km point where I turn into 60 kph speed limit roads, is always better by about 2L/100 that when the jerkiness occurs. All a bit weird but not the spark plugs