The modern world.
The poster can afford a flash car but can't work out the fuel consumption... no wonder the UK is going to the dogs.
Yeah, it's political correctness gone mad, isn't it 🙄
My pub explanation.
"It's simple - Petrol is mainly a mixture of Heptane and Octane, with 7 and 8 carbon chains. The longer the chain the higher the chemical stored energy - more bonds to break requiring energy but considerably more energy released when these rebond with oxygen - exothermic. RON rating (research octane number) indicates the ratio of Heptane to Octane, higher the RON the higher the ratio of longer chain Octane in the fuel so more vvrooom. Mines a Mahito please."
I drove for 6 months on 95 ron and now 10 months on 98 ron. The mileage I'm getting is different
That's enough for seasonal factors to come into play. Petrol engines are more efficient when the air's warm because it's less dense and you need less fuel for stoichiometric ratio. You'll see less power at max throttle, but more economy at normal cruising speeds.
Gonefishin - sounds reasonable, I wonder if the 5th gear test was invalid because the cars didn't have any time to adapt their maps to the new fuel..? And IIRC that was quite a while ago wasn't it?
I drove for 6 months on 95 ron and now 10 months on 98 ron. The mileage I'm getting is different
Perhaps the engine is now run in.......
Switch back to 95 ron for a few months and see if mileage reverts to old figure.
I don't remember the 5th gear test but I do remember one on the Gadget Show that did show a difference, but to be honest I'm not sure that I'd trust either of those shows. All I've pointed out is a [i]possible[/i] mechanism as to why there may be improved performance/economy, it doesn't necessarily mean that there is one. Also, whether or not it is economic to use the more expensive fuel is another question entirely.
I seem to find that V-Power does provide better economy compared to standard fuel. I know the fuel light isn't the most scientific method but from full to light V-Power gives a consistent 30 miles extra, which I reckon easily offsets the extra cost of the fuel.
even BP only claim that you get an average improvement of 13 miles extra per tank, which they put down to lubricating components in the fuel, as well as cleaning elements. Assuming a 600 mile tank (bp are unlikely to have tested this on a small car), that's an improvement of 2% - so in mpg terms - assuming 35mpg, it'd be approx 0.6mpg improvement
http://www.bp.com/sectiongenericarticle.do?categoryId=9018273&contentId=7033278
I expect if some cars magically did an extra 5mpg, bp, shell et al would probably be advertising the fact
How many petrol cars do 600 miles on a tank?
More likely 400 miles which makes it a massive 3% improvement.. 🙂
Still on the Prius that could mean an extra 2mpg if you are lucky.
Do people really get improved performance on 98 ron? IMO its more placebo in terms of acceleration. However it definately makes engines smoother and tends to get more mpg if driven sensibly.
Do people really get improved performance on 98 ron? IMO its more placebo in terms of acceleration.
Should do. See the knock sensor conversation above.
Doesn't apply to older cars and even relatively new motorcycles though.
Perhaps the engine is now run in.......Switch back to 95 ron for a few months and see if mileage reverts to old figure.
Well, the car had 55K on the clock when I got it and now it has 72K. I reckon that's run in enough.
