Premium fuel - Yay or Nay?

[scootr]

That was you in the lawnmower races?

 

[Smartbear]

That was you in the lawnmower races?

I didn’t cut you up did i? :lol:
Rob

 

[Busterboo]

Just been out in the dark to check the fuel cap flap ...

Good news!

It says 'ROZ/RON 95'
Then, even better ...
(ROZ/RON 91-98)

So, now the big question. Where do they sell RON 91? :wink:

 

[Mr Tidy]

So, now the big question. Where do they sell RON 91?

I may be wrong, but I seem to remember seeing 91 for sale in the USA. We don't seem to get anything less than 95 in the UK.

And I may have bought some 91 - after all if it's a rental who cares? :lol:

 

[Busterboo]

 

[Busterboo]

Attached are the state of my exhaust tips after last weekend’s Peak District tour, up & down Dales using the full S54’s rev range vigorously & often, covering approx +500 miles round trip.... where she’s only ever been run on V power (with me 100%)

Running this clean here IMO is all the evidence you need, never had this using other fuels & shows just how good the internals of my S54 are

Nah, you can't fool me. Those pipes are new! Mine are filthy.

 

[PinkPineapple44]

Just been out in the dark to check the fuel cap flap ...

Good news!

It says 'ROZ/RON 95'
Then, even better ...
(ROZ/RON 91-98)

So, now the big question. Where do they sell RON 91? :wink:

I just had to prove you wrong

And you'll find anything down to 87 ron if you head over to America

 

[davemul]

87 octane in the USA is AKI which is the same as 91 RON

 

[Busterboo]

I just had to prove you wrong

You didn't prove me wrong. Your E92 label says 98 (95 - 98), but my E89 label, which is what the thread is about, says 95 (91 - 98).

All I'm doing is following BMW's recommendation.

 

[R60BBA]

V Power everytime.

 

[PinkPineapple44]

I just had to prove you wrong

You didn't prove me wrong. Your E92 label says 98 (95 - 98), but my E89 label, which is what the thread is about, says 95 (91 - 98).

All I'm doing is following BMW's recommendation.

From you're previous comments it seems much more likely you simply don't believe in anything above 95 ron regardless.

My point is BMW (and other manufacturers) do recommend higher ron levels and they do make a difference, but sometimes the difference is greater than others.

 

[Busterboo]

From you're previous comments it seems much more likely you simply don't believe in anything above 95 ron regardless.

I put 98 in my 911 for 5 years, because that's what Porsche recommended. Now, I put 95 in my E89, because that's what BMW recommend. Simples.

 

[PinkPineapple44]

From you're previous comments it seems much more likely you simply don't believe in anything above 95 ron regardless.

I put 98 in my 911 for 5 years, because that's what Porsche recommended. Now, I put 95 in my E89, because that's what BMW recommend. Simples.

Fair enough. I am surprised the N54 only recommends 95 though.

 

[Smartbear]

From you're previous comments it seems much more likely you simply don't believe in anything above 95 ron regardless.

I put 98 in my 911 for 5 years, because that's what Porsche recommended. Now, I put 95 in my E89, because that's what BMW recommend. Simples.

Fair enough. I am surprised the N54 only recommends 95 though.

That’s a minimum recommendation, fine if you want to be a bottom feeder :wink:
Rob

 

[Busterboo]

Dirty boy!

 

[Busterboo]

I put 98 in my 911 for 5 years, because that's what Porsche recommended. Now, I put 95 in my E89, because that's what BMW recommend. Simples.

Fair enough. I am surprised the N54 only recommends 95 though.

That’s a minimum recommendation, fine if you want to be a bottom feeder :wink:
Rob

Actually, Rob, the range is from 91 to 98, but 95 is the recommended. Look on your label.

 

[Anonymous]

 

[PinkPineapple44]

30146006152_ee2100bc28_k.jpg

Is there a 95 ron to 97 comparison too? The difference should be greater than 97 to 99, let alone 95 compared to 99.

 

[MrPT]

Do you know whether those Evolve dyno traces were from back-to-bank tanks of 97 and 99, with no mixing?

I fully subscribe to the idea that some engines can take advantage of higher octane rated fuel, I'm just not sure about the claims that they usually take a couple of tanks to adjust. It seems to me that given there are many other factors, not just RON, that could have an instantaneous effect on pre-ignition levels, it doesn't make any sense for an ECU to slowly make adjustments over time.

 

[Anonymous]

I did some digging around as I tend to use the premium unleaded as well..

Hard evidence in a structured test is hard to get!!

A distillation (pun) of a morning on google suggests:

1) For modern turbo high output engines there is a small gain in BHP for using extra octane.
2) Some 'hairy' NA engines eg Mustang V8 also benefit
3) The cost of the extra HP is out of proportion to the cost increase on the fuel

No damage is done using 'normal' unleaded

To answer the ECU question..the adaption is done in real time without historical trend analysis, unlike some auto boxes