I have run mine on vpower nitro and couldn't fine a shell garage on the m1 so i filled up with bp ultimate and the engine seems to be louder. Its only one tank so it could be placebo, and it hasent made any difference to performance.

I understood that the v power had some added detergents that helped keep the insides a bit cleaner but was only useful on higher mileage engines.

Does Millers provide any evidence for this? or are they reliant on testimonials?

Not sure but I've seen rolling road results on both my Yeti projects to back up the benefit of increased Cetane levels in terms of performance and on brim to brim tests I've done.

Maybe it's more of a benefit of heavily modified cars such as my Yeti Greenline but cleaner burning fuel is a win wether it's water/meth injection or increased Cetane fuel.

Cheers for all the comments folks!

I reckon I'll stick to standard non-supermarket fuel (no more nectar points :( ) with the odd tank of premium stuff (y)

The reason you felt the instant difference on the supermarket fuel is that the engine sensed it beginning to "pink " on the lower quality fuel and retarded the performance to stop the pink. It would the have taken up to 4 tanks of premium fuel to relearn its limits.

I'm not challenging this, buy is this true and verified? As in, readily acknowledged on t'internet? Is there fact to base this somewhere as I'd be very interested in reading up on it. I've wondered, all things being equal and you empty a tank of cheap stuff and fill up on 99ron, how quickly the engine adjusts itself to take advantage of the increased Ron? If at all? Some tuners suggest that you really need a bespoke map to fully utilise the higher Ron.

I have used Sainsbugs diesel on my last four vehicles ,

Astra D 2.0 van + Regal remap  

,Astra F 1.9CDTI van + Regal 200bhp remap ,

2012 VRS dsg

,2014 VRS dsg

For a total of over half a million miles in 9 years

No EGR problems 

No DPF problems 

And in my area Sainsurys is usually 2p/ltr cheaper than all other outlets 

A no brainer for me 

I find in my petrol 2.0tfsi when i use shell vpower nitro + it always gets more miles out of a tank. If it has several tanks filled back to back my car performs better. If i mix it and buy 100ron(shell vpower nitro+) then switch to cheapo 95 ron on my car it suffers and i have owned this car for 6 years this year and every time i do it. I get less miles out of a tank of fuel and the engine doesnt simply like it. I have found when i cant make the effort to go to a shell station that the next best was texaco super unleaded and tesco momentum. The issue is i find that some petrol stations do something because i have tried many places all selling shell vpower nitro+ and i swear some arent giving me shell because i have inconsistent performance from certain garages. I swear half the issue is where you buy it from and whether they are being honest. When you get a garage with vpower nitro+ and its the right stuff my car performs so much better. I would even go as far to say the pumps somehow at the same garage for the same fuel have given me different results. I know people

Will think i am talking **** but it is how its been viewed by me. Its not a placebo effect either.

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I'm not challenging this, buy is this true and verified? As in, readily acknowledged on t'internet? Is there fact to base this somewhere as I'd be very interested in reading up on it. I've wondered, all things being equal and you empty a tank of cheap stuff and fill up on 99ron, how quickly the engine adjusts itself to take advantage of the increased Ron? If at all? Some tuners suggest that you really need a bespoke map to fully utilise the higher Ron.

Look up engine knock.

Basically using higher octane petrol allows for higher combustion temperatures without detonation "pinking" occurring which allows the ecu to run the engine in a more advanced timing map, hence more power.

It constantly try's to run as advanced as possible for maximum output by monitoring the knock sensor and runs the engine just below the knock, when you put better fuel in it mixes with the old fuel you had in the tank so the engine gets a mix of good and normal fuel, it will take up to 3/4 tanks before the fuel the engine recieves is 'pure' v-power so the ecu is running a compromise until then. But performance may show an improvement before then.

If you put a load of normal fuel in, the engine will not be able to run as advanced as its learnt to, so it knocks "pinks" the ecu senses this and retards the timing to a safe basic setting then relearns its limits once again.

All fuel has different properties, so all these people that do these fuel comparisons doing 2 tanks of this and 3 tanks of that don't really understand, I'd do 5 tanks then compare.

If you use a custom map you are telling the ecu that you are only going to use a certain fuel so the minimum it can safely run on is say 97ron so if you put 95ron in it will knock and May not be able to protect itself.

This all only applies to petrol by the way. Diesels by the nature of the engine knock and are designed to cope with it but their operation is completely different.

Edited 2 July, 20169 yr by MrAdamwood

I doubt diesel is any different but v power and tesco momentum is 99 Ron petrol so you will feel a difference.

I ran high power subarus for years and all were mapped on 99 Ron fuel to avoid detting or pinking as it's called and also gave more bhp due to higher ron

Edited 2 July, 20169 yr by tubbytommy

Look up engine knock.

Basically using higher octane petrol allows for higher combustion temperatures without detonation "pinking" occurring which allows the ecu to run the engine in a more advanced timing map, hence more power.

It constantly try's to run as advanced as possible for maximum output by monitoring the knock sensor and runs the engine just below the knock, when you put better fuel in it mixes with the old fuel you had in the tank so the engine gets a mix of good and normal fuel, it will take up to 3/4 tanks before the fuel the engine recieves is 'pure' v-power so the ecu is running a compromise until then. But performance may show an improvement before then.

If you put a load of normal fuel in, the engine will not be able to run as advanced as its learnt to, so it knocks "pinks" the ecu senses this and retards the timing to a safe basic setting then relearns its limits once again.

All fuel has different properties, so all these people that do these fuel comparisons doing 2 tanks of this and 3 tanks of that don't really understand, I'd do 5 tanks then compare.

If you use a custom map you are telling the ecu that you are only going to use a certain fuel so the minimum it can safely run on is say 97ron so if you put 95ron in it will knock and May not be able to protect itself.

This all only applies to petrol by the way. Diesels by the nature of the engine knock and are designed to cope with it but their operation is completely different.

Thanks!

So, my next question is....is the tsi capable of/has a map that will advance the ignition timing to make the most of 99ron IF you were to run it on it pretty much all the time? Sounds liken the answer is yes?

Edited 2 July, 20169 yr by Mallettsmallett

My own experience

Astra 1.9 CDti bought new run exclusively on sainsburys diesel within 18 months (22k miles) needed new inlet manifold, actuator, egr valve, and all associated parts cost £1200 (warranty) there on after ran on shell diesel with no problems px'ed it at 48k miles for a newish 2.0 CDti estate ran that on shell for 34k no issues, the Vrs gets 2 tanks of vpower diesel then 2 tanks of normal shell diesel

Just to throw another few facts in:-

 

Most of the newer petrol engines have variable cams, the 1.4lt 140/150 has & I think the 2.0lt also. The 1.4lt 122/125 & lower have only one vari cam.

 

So those engines with both cams being variable means that the engine really can alter the timing a lot more to suit the load, fuel, etc. & you will see more of a difference on these engines running a high octane fuel!

@MrAdamwood,

You're right.

In the Skoda Octavia owners manual. mk2015:

"Unleaded petrol min. 95 RON / ROZ

Use unleaded fuel with the octane rating 95 RON or higher."

"NOTE: 

• On vehicles using prescribed unleaded petrol of min. 95 RON, the use of petrol with a higher octane number than95 RON can increase the power and reduce fuel consumption."

In the Skoda Octavia owners manual. mk2016:

"Specified petrol is unleaded, min. 95 RON / ROZ

Use the petrol min. 95 RON/ROZ."

"NOTE: 

• On vehicles using the prescribed unleaded petrol of min. 95 ROZ, the use of petrol with a higher octane number than 95 ROZ can lead to an increase in power and reduction in fuel consumption."

The only difference is the disappearance of " or higher". I believe it is a marketing decision. But the notes are identical, so using a higher octane is better for the engine. Also, I think that not everyone has the financial possibility to buy all the time only high octane fuel and discussions like this occur. No offence, it's only my opinion.

Tesco momentum 99 is pretty cheap.

Regarding Audi, Seat and VW owner manuals, I've read them all and in none of them appears a note like that written in Skoda manual. Aren't the same engines? Do you have any ideea?

To me, if the manuals are quoting 95 ron, they must be happy to run on 95, and a higher ron is just an added bonus.

A guy at work said he ran his mk3 golf on premium a couple times, and it made the engine sound awful as it cleaned all the gunk out which was filling any worn gaps.

It seems petrol is clearly better for the reduced knock, but diesel is purely a cleaning agent. I'll try and avoid supermarket diesel, but only use premium every now and again.