I live in England and usually fill my car up with 97 RON fuel
When the tank is filled the computer tells me my range is approximately 260 miles

Well, today I filled up with 99 RON fuel
The computer is now telling me my range is 400 miles!!

Has anyone else experienced anything like this?
I don't think the figures will be very accurate (i hope they are though)

When you guys are talking about octane ratings what measure are you using?
Not RON I guess? - do you measure in MON?
How does the fuel I use compare to yours?

Standard here is 95 RON
Super is 97 RON
And I just tried 99 RON today

It's obviously too early for me to tell if this new fuel is any good - I've only driven 4 miles with it - I guess it'll take 3 tanks before the old stuff is completely flushed out

What experiances do you guys have?

 

It sounds like you cruised in a very efficient manner on the way to the gas station or maybe since last time you cleared your mpg. The car obviously cannot sense what octane you put in it.


MK

 

Higher octane can't possibly give you that much more MPG.. Mine will give me a much larger range if I have been driving the highway and then fill up.

 

Exactly

 

I'm a Brit too, but living in California.

http://en.wikipedia.org/wiki/Octane_rating

Apparently our "Super" gas here (RON+MON/2) 91 is that regular "unleaded" you get in the UK (97 RON). Some places here sell 100 (RON+MON/2) but it's $10 / gallon (reasonable by UK standards for your 99 RON) but people here hate paying that.

Brits in the UK office are really jealous to hear that my gas here costs 57p litre.
**** or not, it's cheap !

 

It turns out your right

It was not my usual station that i filled up in - it was on a motorway (freeway) and I had been crusing along for some time before filling up

I've done 20 miles since filling up yesterday, and the range has come back down to 300 miles so far

 

lol, and you guys still complain about the price, we get it tight!

 

OBTW, we are £1.25 a litre, works out $2.50 US a litre

 

Was often wondering; our cars are designed for 95 RON. So, if we were to put in 89 RON the anti knock detection system would retard the ignition to prevent knocking. But if we were to put in 100 RON what would happen? Is there any benefit at all nowadays where ignition is computer controlled to deviate from manufacturer’s recommendation? I know better octane rating in cars equipped with the carburetors translates into more power but what happens in our cars? Maybe just better cooling?

 

Hi Terminator. If you're racing, there will certainly be a power change for
a range of 'octane' ratings. For simple cruising, the load on the motor is
so low that there should be no pinging for any standard fuel, so there
would be no timing adjustment. Also, the lower 'octane' rating the fuel
has, the more easily combustible it is! Therefore, I would have no qualms
at all driving across country using only U.S. 87-octane fuel, and I would
not be surprised to see better fuel economy with the *cheaper* gas. I
would just avoid any racing on the way.
Joe

 

In a stock vehicle, it won't advance the timing beyond the factory spec if you put in higher octane fuel, so there's no advantage unless you're running in conditions that cause detonation on 95 RON gas (such as the sweltering 120 degree heat of an English summertime ). Aftermarket tuners can modify the software to be more aggressive, at which time you realize the benefit. There is a quantifiable difference between the race gas tune and the standard tune.

 

You got to love the Pmac, lol 120 degrees.

Hey, you should see it right now in Edinburgh, place is full with all these bloody tourists (Edinburgh Festival) they don't come to see our fringe shows, they all come for our glorious weather, lol

 

As long as they're not American, wear puffer jackets and haven't seen Trainspotting they probably don't know what what's going to hit them when they barge into a "lock-in" asking for directions

 

LMFAO, Good one

 

Thought so. Thanks.