Supermarket Fuel, Facts Please

[jagnet]

TooMany2cvs said:

Saab Trionic did that, back in the early 90s.

Yes, and I would class those as the first of the modern petrol turbos as it allowed compression ratios to jump from 7.2:1 to 9.3:1 in the turbo H series engines. Since then CRs have increased a little, eg the Golf R has a 9.6:1 CR, but the basic principals of ignition, fuelling and boost adjustment to maximise efficiency remain the same.

[Pica-Pica]

Supermarket fuel FACT.
Some will never use it.
Some will always use it
Some may use either.

Here endeth the topic.

[M1C]

TooMany2cvs said:

M1C said:

Here's the lovely VBH with some fuel comparisons:

https://www.youtube.com/watch?v=WTaBngvsPrc

<watches first 30sec or so then gets bored>
Christ, but she's let herself go.

That was back in 2012 (i think)

Fuel prices a little bit higher then than now, which is.............nice?!

[manracer]

hepy said:

manracer said:

Couldn't agree more with the above.

My car produced 293bhp with 95 RON and 308 with vpower. Same Dyno, same ambient temp.

Could you tell the difference in power?

100% I could, and still can. Even in my standard Scirocco R I can tell the difference. The way it pulls through the rev range in 2nd through to 4th gear is noticeable. When it comes on boost it feels more forceful and urgent.

No difference whatsoever was observed in my 530i or fiesta ST (1.6t) though.

I've always noticed how VAG turbo cars respond well to higher octane fuels though.

[TooMany2cvs]

M1C said:

TooMany2cvs said:

M1C said:

Here's the lovely VBH with some fuel comparisons:

https://www.youtube.com/watch?v=WTaBngvsPrc

<watches first 30sec or so then gets bored>
Christ, but she's let herself go.

That was back in 2012 (i think)

Fuel prices a little bit higher then than now, which is.............nice?!

I'm not sure there's many parrots flying in the background...

[jagnet]

M1C said:

Here's the lovely VBH with some fuel comparisons:

https://www.youtube.com/watch?v=WTaBngvsPrc

As vaguely interesting as those sorts of tests are they're just a snapshot in the car's life and are more to do with how much peak power is lost through engine adaptation on lower RON fuel. I'd be more interested in seeing long term comparisons between fuels over the life of a car where differences in additive packs might be noticeable in terms of comparative engine performance.

[anonymous-user]

For all of those banging on about Shell petrol, there are only six refineries in the UK and Shell do not actually own any of them. Shell used to own the Essar refinery but sold it in 2011.

Essar Stanlow Refinery
ExxonMobil ExxonMobil Refinery Fawley
PetroIneos Grangemouth Refinery
Phillips 66 Humber Refinery
Total Lindsey Oil Refinery
Valero Pembroke Refinery

So I think we can assume that all petrol stations (supermarket and branded) buy their petrol from whichever refinery is the closest.

People who claim there car runs "like a bag of spanners" on any fuel aside from one particular brand are living in a fantasy land. I used to own an Impreza Turbo back in the day and after reading Scoobynet I used to be obsessed with running it on Super Unleaded. So I filled it with Super and no difference. People on the internet said this was due to the ECU needing to be reset so I did this and still no difference.

Tesco buy their fuel from the same refinery shell and all the others use, it is all the same.

[unsprung]

Roman Rhodes said:

tl:dr pay your money take your choice, no harm in supermarket fuel potential small benefits with some premium brands.

if this dichotomy is accurate -- and many in this thread argue that it is -- then I will not be surprised if Top Tier, or a concept like it, eventually appears in the UK so as to make clear the distinction between "base" and "better"

https://en.wikipedia.org/wiki/Top_Tier_Detergent_G...

[theboss]

I've had 2 BMW x35d / x40d variants and I thought both ran very discernibly quieter and smoother on Shell Vpower diesel than any of the regular products supermarket or not. There may have been a marginal improvement in mpg, I can't remember exactly.

I've had other BMW diesels notably the N47 2.0 twin turbo and a few older 30ds, and found any improvement to be non-existent or unnoticeable so stuck to regular fuel, but in the 35d/ 40d it was very noticeably better.

I regularly put Tesco Momentum and the Costco 99 RON product (allegedly the same?) as well as Vpower in my M5 and don't notice any real difference between them - if there is then its marginal.

[Grayedout]

Thesprucegoose said:

diesel and petrol all comes from the same refineries. they add additives that are blended to the relevant spec. (only real difference is biofuel added)

Correct but it's the addtive pack that does all the work in distiguishing a supermarket fuel from a Shell V-Power !

[TooMany2cvs]

Grayedout said:

Thesprucegoose said:

diesel and petrol all comes from the same refineries. they add additives that are blended to the relevant spec. (only real difference is biofuel added)

Correct but it's the addtive pack that does all the work in distiguishing a supermarket fuel from a Shell V-Power !

Big on homeopathy?

To those who work in the industry - how much additive goes into how much base fuel?

[Grayedout]

Monty Python said:

Given that all fuel sold has to meet BS standards, I can't see how supermarket fuel would cause problems a "premium" fuel wouldn't.

The BS standard only dictates what is in the fuel and it's octane level. There is no BS standard that governs a fuels performance in terms of cleanliness etc.

[Grayedout]

TooMany2cvs said:

Grayedout said:

Thesprucegoose said:

diesel and petrol all comes from the same refineries. they add additives that are blended to the relevant spec. (only real difference is biofuel added)

Correct but it's the addtive pack that does all the work in distiguishing a supermarket fuel from a Shell V-Power !

Big on homeopathy?

To those who work in the industry - how much additive goes into how much base fuel?

Tiny amounts such as 600 ppm (parts per million) but they have a large effect.

The difference between a regular and premium fuel can often just be an increased amount of the same additive.

[Willy Nilly]

My Jazz and CBR600F run perfectly well on Asda fuel and I've never found any difference whatever they are fed on. They've both been abroad and fed on foreign muck, the CBR has been further dining on fuel from France, Belgium, Luxembourg, Germany, Austria and Italy and I can confirm that there is fk all difference

[jagnet]

TooMany2cvs said:

Big on homeopathy?

To those who work in the industry - how much additive goes into how much base fuel?

Whilst I can't claim to work in the industry, this may be of some use:


The Role of Deposit Control Fuel Additives in Automotive Gasoline and Diesel Fuels, Francis H Palmer

It's an interesting read and it does also make reference to friction reduction additives which rarely get mentioned in the supermarket / premium fuels debate.

Hayden et al 2001 said:

The benefit of the gasoline friction modifier fuel additive was generally found at the higher oil temperature conditions. The fuel economy change was immediately measurable and further gains were seen as the friction modifier fuel additive accumulated in the engine oil and reduced friction in oil-wetted parts of the engine. The use of friction modifiers in engine oil formulations did not negate the fuel additive benefit. This program has shown that using the fuel to supply a friction modifier is a practical method to improve vehicle fuel economy.

Hayden, T., Ropes, C., and Rawdon, M., "The Performance of a Gasoline Friction Modifier Fuel Additive," SAE Technical Paper 2001-01-1961, 2001, https://doi.org/10.4271/2001-01-1961.

Given that the piston rings account for ~50% of the frictional losses in an engine, friction reducers added via the fuel are well placed to reduce these losses. The study above found average instantaneous fuel economy improvements of 2% and predicted long term average fuel economy benefits of 3%.

[jagnet]

Going back to Shell's GTL fuels, I did stumble upon this paper on the differences in performance and emissions between diesel, GTL and G50 (50/50 diesel/GTL):

Bassiony Ibrahim El-Kassaby said:

In this paper, the performance and emissions of a diesel engine fueled by the GTL fuel, diesel, GTL-diesel mixture (G50) were experimentally investigated and compared at the engine full load condition and at a constant engine speed of 1700 rpm. The results showed that the GTL fuel has a great potential to be used as a cleaner alternative fuel for the diesel engines. Although using the GTL and G50 fuels decreased slightly the engine maximum power compared to the diesel fuel, both the engine brake thermal efficiency and engine brake specific fuel consumption were improved. Also, the maximum rate of pressure rise decreased. In addition, using the GTL and G50 fuels as alternatives to the diesel resulted in a significant decrease in engine CO, NOx, and SO2 emissions. The amount of reduction in engine emissions and improvement in engine performance varied with engine operating conditions. On average, using the GTL fuel decreased CO, NOx, and SO2 emissions by up to 57%, 30%, and 92%, respectively, compared to diesel fuel. Also, the bsfc decreased by up to 22.8% and the thermal efficiency increased by up to 15.6%.

Bassiony, M., Ibrahim, A., & El-Kassaby, M. (2016). An experimental study on the effect of using gas-to-liquid (GTL) fuel on diesel engine performance and emissions. Alexandria Engineering Journal, 55(3), 2115-2124. doi:10.1016/j.aej.2016.06.026
http://www.sciencedirect.com/science/article/pii/S...

Shell are very coy about how much synthetic GTL is blended with petroleum diesel in V-Power, describing it as a "component". I've drawn a blank on finding any genuine figures, but I did find a graph showing CO2 output against GTL as a percentage of fuel that suggests to me that to get the most CO2 reduction for the least % of GTL then they'd need to be using > 25% GTL in V-Power Diesel:


https://www.dgmk.de/petrochemistry/abstracts_conte...

Versus the small treat rates of additives, I think it's safe to assume that the GTL fuel is the single biggest component added to the standard petroleum diesel base fuel.

[Cold]

Heaveho said:

Cold said:

How do you spell placebo?

Spell it any way you want. It's not the same as having a turbocharged petrol car that's relies on knowing the difference between 95 and 99 RON. If you bothered your arse to measure the difference via knock count or ecu timing, you would know the difference. If you drive a dull sh!tter, it won't matter.

If you really want to guarantee to know the difference, buy a modified turbocharged car mapped to run on 99 RON fuel, fill it with supermarket p!ss, and see how long it hangs together when you kick it's brains in for an extended period of time. Don't moan when you get an engine rebuild related bill, you were warned.

I ran a modified Esprit some years ago that had the expected mods including a replacement engine map, turbo and whatnot. It had an impressive bhp output given the low-def version of the tech available at the time. It was fed whatever fuel was available nearby whether going to the shops or being thrapped around Combe.
I still see the car around in person and on forums and as far as I know it hasn't been rebuilt yet, still on its original internals and turbocharger - although it did have a rear wheel bearing issue a while back which damaged the hub, but I'm not convinced that could be attributed to its fuel supplier.

My dull stter of an Aston is coping fine on supermarket fuel too.

But thanks for the warning. I do enjoy a bit of jeopardy, but you'll note there's no moaning going on here.

[WJNB]

BAM225 said:

Tried to explain this on pistonheads time and time again, I used to do some work at a fuel refinery in fact, but alas people think that shell and bp use wizzardry to make there fuel better and this thread will almost instantly by tomorrow drag into a arguement.

It's the bullst factor & most go for it.
Pretty colours, smart posters & leaflets & waffle about saving points to get a few quid off. I've fallen for this clap-trap at Shell & got sucked in because of the points & there's a station on my doorstep.

[stevesingo]

jagnet said:

Going back to Shell's GTL fuels, I did stumble upon this paper on the differences in performance and emissions between diesel, GTL and G50 (50/50 diesel/GTL):

Bassiony Ibrahim El-Kassaby said:

In this paper, the performance and emissions of a diesel engine fueled by the GTL fuel, diesel, GTL-diesel mixture (G50) were experimentally investigated and compared at the engine full load condition and at a constant engine speed of 1700 rpm. The results showed that the GTL fuel has a great potential to be used as a cleaner alternative fuel for the diesel engines. Although using the GTL and G50 fuels decreased slightly the engine maximum power compared to the diesel fuel, both the engine brake thermal efficiency and engine brake specific fuel consumption were improved. Also, the maximum rate of pressure rise decreased. In addition, using the GTL and G50 fuels as alternatives to the diesel resulted in a significant decrease in engine CO, NOx, and SO2 emissions. The amount of reduction in engine emissions and improvement in engine performance varied with engine operating conditions. On average, using the GTL fuel decreased CO, NOx, and SO2 emissions by up to 57%, 30%, and 92%, respectively, compared to diesel fuel. Also, the bsfc decreased by up to 22.8% and the thermal efficiency increased by up to 15.6%.

Bassiony, M., Ibrahim, A., & El-Kassaby, M. (2016). An experimental study on the effect of using gas-to-liquid (GTL) fuel on diesel engine performance and emissions. Alexandria Engineering Journal, 55(3), 2115-2124. doi:10.1016/j.aej.2016.06.026
http://www.sciencedirect.com/science/article/pii/S...

Shell are very coy about how much synthetic GTL is blended with petroleum diesel in V-Power, describing it as a "component". I've drawn a blank on finding any genuine figures, but I did find a graph showing CO2 output against GTL as a percentage of fuel that suggests to me that to get the most CO2 reduction for the least % of GTL then they'd need to be using > 25% GTL in V-Power Diesel:


https://www.dgmk.de/petrochemistry/abstracts_conte...

Versus the small treat rates of additives, I think it's safe to assume that the GTL fuel is the single biggest component added to the standard petroleum diesel base fuel.

In regard to the bolded, it would be interesting to make a comparison against a fixed, sub-maximal power output, how much an improvement is given for a fixed output?

[jagnet]

These are a couple of graphs from that paper for engine brake specific fuel consumption and thermal efficiency for a given % of max power: