Revolver

Must you keep telling us that Rick!

RIX 8

Oh yeah right - sorry for some perverse reason it makes me feel really good, but i s'pose i sound a bit like a eeekkkk - sorry

Cromax

If you get free petrol ... why not spread it around a bit?

Grizzly8

Rather get a bigger salary package tax free and buy a petrol refinery .

Michael

Revolver

We're just jealous.

clow

I've managed to get about 450 from about 50-52ltrs the last 2 fills actually.

Even on our drive couple weekends ago, I managed to get 400 from it.
Quite impressed.

I usually put in PULP95.

C.

mikeyr

Damn Chris, Rev and I didn't even make it back to Katoomba!! Maybe our 98 was evaporating faster!

clow

Or maybe I wasn't driving it hard enough. Probably the reason there was a train of cars behind me. Heh heh heh.

C.

DarkBrew

I just managed around 10 l/100km on a road trip - cruising 118 km/hr with three people and luggage in the car! My normal mileage is 12.5 to 13.5 l/100km.

Revolver

Actually, I still had about quarter of a tank. It was more a need to expel liquid that caused me to call a stop.

timbo

I'm sorry guys, but I find the "I get xxx kms from a tank" comments to be almost totally meaningless. There are so many variables which affect each tank range measure, including the season, fuel brew and ambient temps.

I was totally and unashamedly **** in running an electronic log book while I had my 8, and can tell you categorically that in the driving style and mix that I did:

- Long term average fuel economy for the 8, over 61,000k was 12.6L/100k -- yes, I will probably be called to give evidence on behalf of MA if anyone takes them to court over misleading fuel economy claims -- my car did what it said on the box
- Worst, excluding track days was 14.7L/100k -- what I call crappy urban driving
- Very spirited driving (AKA track work) with lots of WOT, will run you into 25+L/100k...no worries (but it's fun!)
- Best, secured on double demerit long weekend trip with cruise glued to 110kph, was 9.8L/100k

That was my car, with me driving, over the trips and use I did -- yours will be different.

Now, I'll shut up, but before doing that I just want you to know that the Polo, under exactly the same conditions (and with the same point to point times)...is averaging 7.8L/100k

Revolver

Yes, but it still looks half as good too.

As for times, have you tracked it yet Timbo?

timbo

True, but evidence suggests it'll depreciate half as slowly

Not tracked yet, but MACCAA & I are looking to make some time

Revolver

Oh, it'll depreciate just as quickly. We've just got farther to fall.

Look forward to hearing comparable track times (i.e. Wakefield) in due course.

Rotor Convert

Who cares about fuel economy! My Accountant tells me I have to spend more $$ on the car!! So heavy on the right foot will be me. Love wizzing away from the traffic lights getting up to 60 warp speed and then buttoning off...

Get an Accountant like mine..lease the car and settle in for fun miles!

Cromax

I don't really mind ... the RX8's seriously no worse than a mid-capacity V8 so why complain about it? If you're using too much petrol, take it easy on the accelerator!

I try to take it easy most of the time, but I get the urge to pump the accelerator ... especially when going around the twisties on the way home from work

Oh yer, optimax extreme gets the thumbs up for economy.

auzoom

I've been meaning to ask if anyone saw the segment on ACA or was it Today Tonight about Optimax extreme...

For those that didnt its an E10 mix, meaning it is 10% ethanol. But its 100RON octane. SO we get a more predictable flame front but less dense fuel...yet we have to pay, is it 15c/litre, more for it?

Cromax, I am not doubting your economy rating of 2 thumbs up but I dont see how it can be more economic when its a less energy dense fuel.

Cromax

I'm not sure what they said on ACA and TT, but most of their stories on this stuff is sensationalised garbage to make people watch.

Essentially, by lower density, you're talking about 4kg/m^3 ... that is absolutley nothing! Therefore the difference in density between the regular and extreme optimax is minimal, if not negligable. The end boiling points are both 196ºC and they both contain roughly the same amount of sulpher. Benzine levels are higher on Extreme though, meaning it burns a bit cleaner ... and it has a higher RON of 100.4 instead of 98.4.

Here's the TDS for them:
http://www.shell.com/static/au-en/do...ptimax_tds.pdf
http://www.shell.com/static/au-en/do...xtreme_tds.pdf

timbo

I'd be interested if you have any data to support the claim that using Optimax extreme results in better fuel consumption figures.

I certainly tested various 98s vs 95s and found absolutely no difference in results

There have been various threads on this. The scientific explanation (simplified) is that while you may get better figures with a normal reciprocating engine, octane rating does not have the same effect on rotary combustion.

My advice: save your money and use a 'good' 95

Revolver

I agree - use 95 and bury the foot at every responsible opportunity.

Life's too short to overanalyse whether you're spending $10 more on fuel each week than the next guy.

auzoom

Sorry didnt mean that to come out as if I actually believed what was said, just relaying what I saw.

Just gone back over what I read previously on this. Please realise I am a scientific dunce so I may not have the correct interpretation. The figures I was remembering were MJ/Ltr which for regular fuel is apparantly 32. Ethanol is about 20 and E10 ends up being 28 which is a 12.5% loss of energy over non blended fuel. So it would need to be a lot cleaner to make up for that sort of loss.

Or have I totally misunderstood it all?

Gibbo

I love fuel economy talks of regular versus premium unleaded. For all those Opticrap...oops I mean Optimax extreme fans, do me a favour are you getting 10% better fuel economy from it, because that is what you are paying at the pump. The answer is always no, performance is also questionable.

BTW extreme is 5% ethanol not 10%, government regulations allow 10%.

auzoom

Ya see, now you've gone and messed up all my arithmatic

Cromax

They haven't just gone and added 5% of ethanol to a tank full of optimax. They've played with the structure of each to make sure the density isn't affected.

I find it smoother than Optimax 98, and I really don't care about the extra cost, as the amount you're talking about is negligable. I prefer not to drive with my foot buried on the accelerator as I do want to keep this car as long as I possibly can.

Gibbo

Three words in response to that;

"BUY A VOLVO"

You bought the wrong car if you don't want to bury the foot.