Do Performance Fuels Make A Difference? - Fifth Gear

Vicki finds out if expensive performance fuels can actually make a car run better.

[Edwinedwin]

You can really really feel those 5 extra hp while being stuck in London traffic behind an old focus.

[MDS]

Switching from 95 to 99 v power made a WORLD of difference to my FSi engine. Any engine with injectors should be run on 99. Better throttle response and runs so much smoothly. I couldnt believe how much of a difference it made. Even got a few more MPGs! Highly recommend guys.

[Can-Am]

1.45 pounds per liter? I will never complain about fuel prices again.

[xwildcard]

Higher octane fuels are *NOT* designed to provide higher performance. This is yet another video contributing to that myth. Despite their acknowledgment of the facts they go on pretending like they should see an increase in power, which is not the case. Octane makes gasoline more resilient to spontaneous combustion due to pressure. Engines with high compression ratios need higher octane fuels to prevent the fuel from igniting before top dead center, introducing knock which can quickly damage or destroy conrods and the crank. Octane does *NOT* make gasoline's combustion release more energy. The *ONLY* power increase you will ever see is in a vehicle who's ECU adjusting to make use of the fuel. These gains would be so minimal as to essentially be within any methodology's margin of error. This power increase will come from adjusted ignition timing, not from the fuel.

In the States (and possibly other countries) Octane rating uses the acronym AKI. AKI stands for anti-knock index. It isn't about power, it's about getting the gasoline to not detonate on the compression stroke. Buying premium fuels when your car is built for normal fuels is not only a waste of money, but in a vehicle that doesn't have the capability to adjust may actually be causing additional carbon buildup over time and causing problems. Obviously, the VW engine in this GTI isn't one of those vehicles, but the point remains.

Lastly, by using a different brand for every test they completely invalidate their testing. They should have used a high- and low-AKI fuel from each vendor and compared them against each other, not across brands. Seeing an increase in power using this methodology could simply be a result of gas quality across brands rather than Octane content.

[Alexandra-Rex]

Vicki shouldn't have known which fuel she had in the test runs until it was all over.

[jamesmeek]

I’ve put V Power in my Vauxhall Astra 1.8i Sri 57 plate the other day . I didn’t put it in to get any extra power . I put it in Just for the cleaning capabilities . The car runs smoother and picks up a lot better . Probably because the V power as given the engine a good clean and restored my engine back to factory settings ? Anyway I’m happy with how the car is running now rather than on Shell fuel save . So I’m happy to pay the extra per tank just for maintenance purposes 👍

[omfgwtfbbq]

I think you are gonna feel the decrease on your bank account more than you can feel the tiny increase in power lol

[Half_Centaur]

For any Americans who watched this and, like me, thought that these octane ratings were incredibly high, I looked into it and, apparently, we use a different octane rating system than most of the rest of the world (of course we do). AKI (Anti-Knock Index) is used in the US and RON is used basically everywhere else. AKI ratings are generally a few points lower than RON, but the actual quality of the fuels is almost identical.

[jasonjudge]

they fail to explain the benefits of the premium fuels burning cleaner and keeping injector jets cleaner it's not all about the performance also they should have tested tescos premium momentum at 100 Ron

[MHKB]

Would love to see this done again on Diesels showing mpg differences.

[Connor-kdmv]

The ECU would take a while to adjust timing/compression. Seems pretty flawed to assume it’s instant.

[FatRakoon]

I did a little trial on my Kawasaki ZZR a few years ago, with Shell and Shell V-Power, and I am really sure that the V-Power helped the engine run somewhat better and more responsive.
I ran it mostly on stock fuel and only now and again, I would plop some V-Power in and I was sure that it helped it.

It may very well have been placebo though?

[JJ_ExMachina]

The main issue with this sort of test is you are relying on the vehicle (in stock form) to advance its own timing to take advantage of the added octane. However if you were to do a software upgrade and tune the engine properly for the fuel you were using, you would most certainly see a huge increase in performance over all. The VW does a descant job at detecting the octane (RON) of the fuel, since there is a notable difference in power output, otherwise there would have been no difference. The issue here is what type of vehicle you are using and how it is set up from the factory. A naturally aspirated vehicle with standard compression would not really benefit from a high octane (RON) fuel. However high compression vehicles like the Toyota GT86 or sport bikes like the ZX6R will see a difference (high compression engines can not run lower octane (RON) fuels with out causing damage). Forced induction vehicles are even more flexible then high compression ones, since the amount of "compression" the engine would see is dependent on how much boost there is. That is something that can be easily controlled by the computer and thus take advantage of the higher octane (RON) fuels.

[MC_AU]

Australia: I did the mpg test several years ago with ULP 91/95/98 RON. Same brand.
My standard load was 95, and ran approx 2000km mixed cycle of roads & traffic.
I refilled with 98, and another 2000km mixed cycle.
91 was ignored at the time as MY06 180KW car was engineered for PULP
Result was 12% higher cost vs 16% better economy.
I was getting 4% for free with nothing more than stopping at a different pump.

[SeverityOne]

Some months ago, we got 98 RON fuel here in Malta, in addition to 95 RON. So I decided to give it a try in my 1.4L Turbo Opel Astra GTC. Perceptively, the car performs a little bit better, and throttle response is better. Something that can be accurately measured is that the increased fuel economy balances out the €0.15 extra you pay per litre. So I still get to drive the same number of days with €50 worth of fuel, but since I can fuel up more now, I don't have to fuel up so often, and my car performs slightly better.

[m.d.f]

The comparison should have included:
1. Fuel efficiency -mpg
2. Effects of the fuel to the engine as advertised (clean the engine etc)
3. Performance (which is the only one tested and shown here)

[jumbaleo]

I occasionally used to run (what was Shell Optimax) many years ago in an old Peugeot 309, 1.3 litre. The difference between running standard petrol and Optimax was huge. So much so that when I sold the car the new owner was convinced I had fettled with the engine which was not true. It sounds crazy but the performance was amasing. So I would say you are really going to notice more of a difference in a standard family type car rather than something that is already supposed to be a performance car.

Also, the performance change was also almost instantaneous, filling up an empty tank with the Vmax you would feel a difference within a few miles.

When I moved on to a standard Ford KA a year or so later I would go through a phase of every three or four months just filling up with Vmax, and I would definitely get more miles per tank after prolonged usage, although, as it was more expensive their was little point in using it for the purposes of economy alone.

[dougsullivan]

Interestingly, a few years ago, my wife owned a Daihatsu Charade. I took it out a few times and felt that it was a bit sluggish. I let the tank (nearly) empty and then filled it with premium unleaded. The difference was quite remarkable. On std unleaded, the engine needed to rev up to 2500rpm before changing up a gear. If you didn't reach 2500rpm, the engine would struggle in the next gear up. Once on premium unleaded, that 2500rpm dropped almost exactly to 2000rpm where I could change up a gear quite comfortably. This was a consistent result over several tanks of fuel. The consumption figures improved quite a bit and the engine just felt 'happier'and more responsive on the premium fuel.
I have since done similar tests on more recent cars that I have owned but I have been unable to notice any discernible difference between fuels. My more recent cars have been bigger and more powerful (not hard compared to the Charade) and would certainly have better engine management systems.
In all, I would say that a car like the Golf GTI fits that latter power and better management. So the premium fuels may be better justified in lower powered older cars. I also know that the premium fuels go 'off' quicker because of the additives. So, if you don't use your car regularly, cheaper fuels are better anyway.

[jazedftw]

I drive a BMW 120d 2014.
When filled up with V Power Diesel, there is definitely a difference in driving.
Car doesn't feel faster but it feels as if it accelerates with less effort.
It is definitely good for keeping the injectors clean aswell!
I use this gas every 10 fuel tanks to help keep the injectors clean.

[DBGMLV]

On a stock engine it doesn't make a differnce. However if do a remap using higher octane fuel means you can push the engine further while not blowing it up.