The US (And Canada, Brazil and a few more) use AKI instead of RON. So premium US 91-94 equals UK 97-100

And despite that as good as equality, it is not uncommon for similar engines to have a slight detune for the US market as well.

I dunno, they call everything the wrong name, have a different size of gallon and now can't sort out an octane....  Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Mulcher wrote:

Regular 95 octane for my 4.2 SC and there’s never been a hint of pinking.

Haylands wrote:

I dunno, they call everything the wrong name, have a different size of gallon and now can't sort out an octane....

Well we do have a proper gallon in Canada but you know we have been metric for ages. Here I use Chevron Premium which I think is 99. They have a. Supper Premium but don't use that. All these cars have knock sensors so I wouldn't think you would get any pinging, at least not for long. If you going up a steep hill or towing a load and the engine detected pinging it would retard the ignition and you would end up with less power.

As recently documented on here, I had an injector fail on my 5.0 L405.

I doubt very much if running exclusively on Super would have made a difference, but who knows!!

I fill up at my local garage which has 24 pumps available, but only 6 have Super. The worst thing being they’re all at the front of the line, which means at busy times it can be a PITA to get on them.

My choices moving forward are to fill up at unsociable hours or be a nuisance at fill up time

I have the SDV8, but I have owned SC V8’s before and would definitely run an SC FFRR on Shell V-Power.

[quote="Strider"]Always use use Shell V-Power Premium in my 4.2 SC , never used anything else so cant compare.

Same here  1983 Range Rover Classic red CHP 723Y
H81 MFX Classic
1995 P38 4.6 HSE
2006 L322 V8 Vogue supercharged

Back to ASDA it is then....

https://www.which.co.uk/news/2020/09/super...7Q67SoOyIo Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Err not really. My takeaways from that were:

All base fuels are made to the same standard - we knew that, its got a BS number and everything.
All brands add different proprietary additives and more of them are added to "Super" - yep that's what we all have said.
All modern UK cars can run on 95Ron without issue, but the best and most powerful will run better on "Super"- yep we said that too.
If you want to save money on fuel buy an economical car and drive economically - Good advice. Mike - MPx

2017 5.0 V8 Supercharged SVAutobigraphy Dynamic SVO Palette Grey (2021-...)
2012 5.0 V8 Supercharged Autoboigraphy Orkney Grey (2017-2021)
2007 4.2 V8 Supercharged Vogue SE Tonga Green (2012-2017)
2002 4.4 V8 Vogue Bonnatti Grey (2008-2012)

Not quite
"All modern UK cars can run on 95Ron without issue, but the best and most powerful will run better on "Super"- yep we said that too."

It actually said was

"the key difference between regular and ‘super unleaded’ is its higher octane rating. In the UK, normal unleaded is rated at 95 RON (Research Octane Number) Whereas super unleaded is normally between 97 to 99 RON.

Essentially this means the super-unleaded fuel can be compressed more in an engine without prematurely igniting. Using normal unleaded in cars requiring higher octane fuel can cause engine knock – where the fuel fires before the completion of the compression cycle (you may hear it as a ‘ping’).

There’s no harm in using super unleaded, even if high octane isn’t recommended. But you’re unlikely to detect any benefit unless your car specifically requires it – normally very high-performance and some imported vehicles."

Your engine and was designed to run on 95 RON, you will see very little difference between super and standard unleaded other than the placebo effect. The fuel companies brainwashing works well LOL BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

I've got some cars that run on V-Power, and some that get regular. V-Power is for performance reasons for me - I've got one car specifically mapped on it and the other uses it because it gets premixed with 2 stroke oil so it helps combat the effective RON drop of it.

The Range Rover gets the standard stuff as at less than 100bhp per litre, I don't see it as trying particularly hard so shouldn't be anywhere close to knocking.

All the cars get Shell fuels rather than supermarket stuff to take advantage of some of the additives. I've seen the inside of an engine that did 140k of supermarket fuel It was considerably better the next time I took the engine apart having run it on V-Power.

Shell just happens to be my local station rather than an affection for the brand though.

AJGalaxy2012 wrote:

Not quite

But you’re unlikely to detect any benefit unless your car specifically requires it – normally very high-performance and some imported vehicles."

Your engine and was designed to run on 95 RON, you will see very little difference between super and standard unleaded other than the placebo effect. The fuel companies brainwashing works well LOL

And what I said in an earlier post was "a marginal but real improvement". Powerful cars like ours have knock sensors - the ECU can advance ignition until knock is detected. Advanced ignition under hard acceleration will give a marginal increase in performance. Our cars have this, indeed most cars with an ECU do, that's what the mapping is all about. I completely agree that for many/most this marginal increase isn't "worth" it. My point is that paying over £100k for the car to get at best 26mpg isn't "worth" it over a not much lesser vehicle if money is the significant deciding factor. But if you've made the leap with the big bucks to get "the best", then paying a few cents more for the best fuels doesn't seem like much of an extra step to me - indeed the opposite, if it was worth an extra £30k to get 550bhp instead of 500bhp then the real equivalence of an an extra handful of bhp under hard acceleration will be cheap at £10 per fill.

...and yes, I've fallen for it...my nephew works for Shell  Mike - MPx

2017 5.0 V8 Supercharged SVAutobigraphy Dynamic SVO Palette Grey (2021-...)
2012 5.0 V8 Supercharged Autoboigraphy Orkney Grey (2017-2021)
2007 4.2 V8 Supercharged Vogue SE Tonga Green (2012-2017)
2002 4.4 V8 Vogue Bonnatti Grey (2008-2012)

I think if it was me I would stick 95 in it, let's be honest an SC is not exactly a sports car and could anyone really feel the few extra HP that super unleaded is going to give you? I have driven a handful of cars where 98+ is specified by the manufacturer, the only reason I stick to a fuel grade is when the tune expects it (I had an RS4 once that hated 95RON fuel).

5th Gear did a great fuel comparison video a few years back on a Golf GTI, its worth a look...then make your own mind up.
https://www.youtube.com/watch?v=d8L-X89duEs 2021 L405 Vogue D300
2016 L405 Vogue 3.0TDV6 (Sold)

Just how much time can you really be at full throttle? It’s the only time any difference exists, I doubt that the extra horsepower can be sensed by anyone to be honest. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6