Posh Petrol

SLC206

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Fellow Frogger
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Here's a clip from Fifth Gear (24 Sept) about 95 vs 98 (or so) RON fuel.

Apologies for the FLOG.

 
Interesting Video.

I have often wondered the same.

It would be interesting to see a comparison between 91 vs 95/98 in a car that "requires at least 95 ron petrol"... ie my 407.

I have often wondered if I can run the car on 91 safely,

shobbz
 
Interesting Video.

I have often wondered the same.

It would be interesting to see a comparison between 91 vs 95/98 in a car that "requires at least 95 ron petrol"... ie my 407.

I have often wondered if I can run the car on 91 safely,

shobbz

The UK and European standard for petrol specifies a minimum RON of 95 and a minimum MON of 85, so this is what their vehicles are designed to run on. Essentially, their 'regular unleaded' is the equivalent of our 'premium unleaded'.

In Australia, USA and Japan, the minimum RON is typically 91 RON, which again, explains why the majority of these vehicles can run on 'our' regular unleaded.

I suppose using 91 in a car designed to use 95 would be analogous to using 87 in a car designed for 91 - it would probably run, but very poorly.
 
I can tell you that using a lower grade petrol in my 2001 RX4 resulted in worse fuel consumption and a significant loss of performance. I could obtain up to 8.3 litres/100km in suburban traffic on 98 unleaded, but it dropped by about 0.7l/100km using a lower grade. The electronic management system self adjusted for the lower octane, the engine still ran beautifully, just not the same zip or economy.
 
There is a big hole in the testing as it did not include fuel "economy". The anecdotal evidence often given, and I believe the test results from various other sources, have suggested that fuels with a higher RON will tend to give better economy, offsetting the additional cost. In addition, as was noted, the "posh" fuels claim to have some cleaning properties which may well equate to lower running costs long term.

http://www.mynrmacommunity.com/motoring/2011/06/24/fuels-which-should-you-use/
 
One certainly feels the difference in a 2CV which has no engine management systems. Likewise a BX 19TRi, which pinged on 95 but not 98. Our 91 with ethanol is in another category. Yeah, the 2CV has run on that and on OPAL petrol, but I only use exotic crap in the bush where I have no option.

If I leave a 2CV standing for a couple of months, I drain the fuel (because it won't start the car) and stick it in the Xantia. Then fill the Xantia with 98 and let the engine management system digest it.

If I want cheaper petrol, I time my refuelling days to the low points in the cycle.

John
 
There is a big hole in the testing as it did not include fuel "economy".
I don't believe Fifth Gear (or Top Gear, for that matter) viewers are the slightest bit interested in economy. It just wasn't part of the brief.

But it's true in my experience. The 306 was much happier (the pinging from day one ceased) and went at least 50km further on 98 than 95 (Optimax had only just arrived when I had it, and it was the only 98 RON fuel in Oz).

Conversely, the 206 GTi and GTi180 made no difference to performance or economy between 95 and 98 RON.
 
I have come across the claim somewhere that "all" petrol is refined as 95, and that 91 is 95 that didn't make the grade when tested to be fully rated as 95. Or in other words, 95 is guaranteed to be 95, but the 91 you buy could well be identical to 95 - or, alternatively, could be rated as anything between 91 and 95.
I can't recall if the same deal applied to 98, or indeed if the chain started from 98: 98 = 98, 95 = not quite as good 98, 91 = a but more not quite as good 98.

Clear as mud?
 
Carsguide had a story a couple of weeks back where they ran an SUV on the 4 fuels over the same route, during the same conditions, with the same driver and compared the differences.
From memoury the results were something like this:-
98 gave the best result in economy and performance. And it was recommended that european and performance cars use this as this is what their engines are tuned to run on.
The 91 had a little less milage and was a little down on performance. But it was mentioned that it runs well in Aussie, Korean & Japanese cars as they are tuned to run on 91. They said putting 98 into a bog standard Commodore for example was a waste of money, as there is no noticable improvement in econonmy or performance.
The E10 offered a little less milage again, but there was no change in performance because it has a 91 octane rating. It was also said that the stories you hear about engine damage due to corrosion are now false, because there is an additive added now to prevent this.
They also tried the E85 and this offered even less milage. The only thing E85 had to offer was less polutents.
They said for E85 to be equivalent to the 91, it needed to be sell at about 40¢ a litre less to make up for the lack of milage.
The E10 should be around 8¢ a litre less than regular 91 and 98 although offering better economy, the economy doesn't match the price difference and it would leave you out of pocket by about $120 over the course of a year!
After reading that, I went from putting E10 to 98 in my Barina and I have noticed I get about an extra 50Km out of a tank, the wife's Commodore now just gets regular 91, with no noticable differences.
 
They said for E85 to be equivalent to the 91, it needed to be sell at about 40¢ a litre less to make up for the lack of milage.

That was exactly what i found.
At first i though 'great, subsidised fuel' then the reality that it was me who was subsidising the sugar industry hit home prety quickly.
It got better though, because my catch can resevoir filled with sump snot really quickly, so if you are doing short trips and not getting the oil up to temp, I cant see how engine damage would be avoided.
Then there was the corrosive nature of the fuel, which i accidentally spilled on my acrylic paint....Doh.

About the only good thing was the smell of the exhaust and the smug feeling that my old car could do something that all those expensive new cars could not do.

I ended up having a gerry can spare when i stopped using it, and it makes a great parts cleaner.

Jo
 
To use E85 on a 2CV, requires a special tuning needle to get it to idle and run.

Fortunately, being a democracy, you can use whatever petrol you want. I imagine the dawdlers and valium induced drivers would be happy on anything, particularly if they are peak hour commuters just polluting the atmosphere.

The more spirited drivers are prepared to pay the extra for the 98 RON, as they are prepared to pay the extra for the odd speeding fine. Its horses for courses, or durr cheveaux as the French would say.

John
 
To use E85 on a 2CV, requires a special tuning needle to get it to idle and run.

Fortunately, being a democracy, you can use whatever petrol you want.
John

I'm not so sure about the legalities of owner modifying your car to use e85.
I also suspect there would be a stack of rubber and non coated steel parts in a 2cv that would not enjoy the extra potential moisture and corrosive tendencies of the e85.
The only advantage I can see in using e85 is to those turbo gang who want to squeeze an extra 1/4 second out of their car on the drag strip.

Jo
 
This E85 needle assembly was introduced for the Swedish market some years ago. I definately wouldn't be interested.

I wish they still sold the old Super petrol, where I could start the 2CV after three months of non use.

John
 
I have mostly used BP Ultimate in my high compression bikes and the much modded BMW 2002, and modded 16TS powered 4CV, and find if it sits for a month or so the petrol must go off as particularly my Yamaha XT500, and '70 Triumph Bonneville will ping. Maybe I will start using the Shell V Power.
 
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