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Model specific boards => Golf mk7 => Topic started by: BlinGTIes on 01 February 2019, 16:21

Title: Leaded and super unleaded mpg
Post by: BlinGTIes on 01 February 2019, 16:21
Hi guys,

I tried filling my MK 7.5 super unleaded the other week, i did notice a slight improvement in performance. I have gone back to regular unleaded now and have noticed I am going through that at a faster rate than before.

Has anyone else experienced this when they switch from super? Is this normal? If so, how long does it last?

Or have I done something I shouldn’t have!
Title: Re: Leaded and super unleaded mpg
Post by: DTX3 on 01 February 2019, 16:40
I've used nothing but Shell v-power. So can't compare to regular. But I would say that doesn't sound right.

I remember seeing this a few years back https://www.youtube.com/watch?v=d8L-X89duEs
Title: Re: Leaded and super unleaded mpg
Post by: dubber36 on 01 February 2019, 17:03
The colder weather will be why you are using more fuel. Longer to warm up. Heaters and lights on etc.
Title: Re: Leaded and super unleaded mpg
Post by: kmpowell on 01 February 2019, 18:24
As advised by VW, the GTI and R both run best on 98+, which means they are mapped specifically for higher octane fuels. You can put normal 95 in but you’ll get less MPG and less than optimal performance.

I personally only ever use V-Power.
Title: Re: Leaded and super unleaded mpg
Post by: Talk-torque on 01 February 2019, 18:31
^^^^ What he said. You bought a performance car, which was set up to run best on performance fuel. It will run on 95, but at disadvantageous performance and consumption. Whether the cost is worth it is up to you.
Title: Re: Leaded and super unleaded mpg
Post by: Jim_mk7.5 on 01 February 2019, 18:44
Another topic widely debated on here!

Inside the filler cap it tells you what to use. 95 Ron min for the GTI, I believe the R says 97/8.
Title: Re: Leaded and super unleaded mpg
Post by: Watts on 01 February 2019, 18:52
VW do actually recommend super unleaded for the GTI, however it will run on 95 hence why it has that on the cap. I was sceptical but decided to change based on VW advice. I haven't noticed any improvement in economy and a marginal difference in running however for £2.50 extra a tank I don't think it's worth worrying about. I use Momentum 99.
Title: Re: Leaded and super unleaded mpg
Post by: Jim_mk7.5 on 01 February 2019, 18:55
Yes Tesco 99 about 1.21 a litre here although normal down to 1.149 at Texaco locally. But yes, only a few £s extra per tank  :smiley:
Title: Re: Leaded and super unleaded mpg
Post by: monkeyhanger on 01 February 2019, 19:09
VW do actually recommend super unleaded for the GTI, however it will run on 95 hence why it has that on the cap. I was sceptical but decided to change based on VW advice. I haven't noticed any improvement in economy and a marginal difference in running however for £2.50 extra a tank I don't think it's worth worrying about. I use Momentum 99.

Most of Europe calls RON95 "Super", as denoted by the multitude of languages telling you to fill your GTI with "Super" RON 95 on the filler flap. The R  filler flap sticker tells you to use 97/98.

If you haven't seen any improvement in economy swapping to RON99 then it's not set up for it and you're effectively compressing your RON99 to less than optimum before the spark plug ignites it. If set up for RON98, it would be thirstier using RON95.

Plenty of people think RON99 is more calorific than RON95 - it isn't, it just has combustible additives that make the mix less volatile and so can be compressed further without pinking. You're just chucking £2.50 a tank away.

Most of the performance engines around the MK5 era were optimised for RON98, the MK7 GTI engine isn't.
Title: Re: Leaded and super unleaded mpg
Post by: Watts on 01 February 2019, 19:33
VW do actually recommend super unleaded for the GTI, however it will run on 95 hence why it has that on the cap. I was sceptical but decided to change based on VW advice. I haven't noticed any improvement in economy and a marginal difference in running however for £2.50 extra a tank I don't think it's worth worrying about. I use Momentum 99.

Most of Europe calls RON95 "Super", as denoted by the multitude of languages telling you to fill your GTI with "Super" RON 95 on the filler flap. The R  filler flap sticker tells you to use 97/98.

If you haven't seen any improvement in economy swapping to RON99 then it's not set up for it and you're effectively compressing your RON99 to less than optimum before the spark plug ignites it. If set up for RON98, it would be thirstier using RON95.

Plenty of people think RON99 is more calorific than RON95 - it isn't, it just has combustible additives that make the mix less volatile and so can be compressed further without pinking. You're just chucking £2.50 a tank away.

Most of the performance engines around the MK5 era were optimised for RON98, the MK7 GTI engine isn't.

You may well be right, tbh I've no idea. But VW recommend it so that's what I'm doing.

https://www.volkswagen.co.uk/need-help/owners/Fuel

When I reach the point when I can't afford to lose £2.50 a month then I may reconsider :rolleyes:
Title: Re: Leaded and super unleaded mpg
Post by: Ryan90GTI on 01 February 2019, 20:42
I've found I get slightly better economy out of Momentum99 compared to V-Power.

The car feels more responsive with V-Power but only slightly.

1.209 - Momentum 99
1.279 - V-Power

I'm putting in £55-£60 in the car 6 days

If you feel V-Power is too expensive, Momentum 99 is the next best IMO. I was talking to the VW tech last time I was in and they're getting loads of issues with MK6's through owners using poor fuel.
Title: Re: Leaded and super unleaded mpg
Post by: BlinGTIes on 01 February 2019, 23:35
Sorry guys, I wasn’t being clear.

I have always used 95 since I got the car a year ago. I just decided to try super the other week to see if there was any difference. It was marginal. I went back onto the 95 and have found it isn’t as economical as when I was using it before.

The range read out seems to be decreasing twice as fast as the actual miles I’m doing! I don’t remember this happening before. Could it be because of the cold too? Or fact I have switched from super to regular and it will take a while for the engine to ‘recalibrate’ itself to burn it more efficiently?

Title: Re: Leaded and super unleaded mpg
Post by: Ryan90GTI on 02 February 2019, 09:36
It'll be because of how cold it is I would imagine. I get roughly 40-50 miles less per tank in the winter.
Title: Re: Leaded and super unleaded mpg
Post by: Grahamt on 06 February 2019, 06:27

[/quote]

When I reach the point when I can't afford to lose £2.50 a month then I may reconsider :rolleyes:
[/quote]

Indeed........if I ever get to that point the GTI will be history 😂😂😂

Oh forgot it's not even real yet.......still running a Mk4 Tdi, 190k, owned from new in 2003, never ever failed best car ever. I'm sure the new one won't be as reliable with all the complexities of modern cars, dsg, gasoline particulate filters and goodness only knows what other stuff I don't really need but I'm still looking  forward to getting it, delivery mid March I'm told.
Title: Re: Leaded and super unleaded mpg
Post by: neepy7.5 on 06 February 2019, 16:38
If you've got a costco card then fill up on their RON99 super unleaded for the same price as regular unleaded at the local supermarket, it's all i've used since getting the car.
Title: Re: Leaded and super unleaded mpg
Post by: Crockers on 11 February 2019, 20:52
I wonder how much the perception of extra performance is just that...a perception.

I can remember when a spring broke on my Mercedes. I asked them to fit new tyres of a different make at the same time. On the way home I thought the tyres were much better. When I got home I looked at them and realised they had forgotten to change the tyres.

Perception.
Title: Re: Leaded and super unleaded mpg
Post by: mcmaddy on 11 February 2019, 22:42
Everyone has an opinion on this but I use shell V power purely for the additives and the hope it's going to keep the engine cleaner than using supermarket fuel. Plus every article in VW Driver for example always advocates using a good quality fuel.
Title: Re: Leaded and super unleaded mpg
Post by: Simeon on 12 February 2019, 09:17
I wonder how much the perception of extra performance is just that...a perception.

I can remember when a spring broke on my Mercedes. I asked them to fit new tyres of a different make at the same time. On the way home I thought the tyres were much better. When I got home I looked at them and realised they had forgotten to change the tyres.

Perception.

Whoops, presumably you had paid for the tyres too :laugh: