Big Grin,

Nice to hear from another new RX-8 owner.

You now need to join the happy band over at the RX-8 owners club to get even more benefit from your car and to increase the size of that grin.

 

.....thanks Guys for putting Velocity RedRX8 right in my absence. Thats why I showed the worknig out, so that someone could question/confirm my maths.

I mean, a first class honours degree in it doesn't mean I can add up, quite the reverse!

Si

 

Good shout Harrizone - welcome Big Grin, and hope you join the gang on the owners club forum.

 

I've got 20.8 mpg (225 miles from 49.2 litres) from my first tankfull, but this may not be very accurate as it was originally filled by the dealer so I don't know whether it was filled to the first click or if they squeezed some more in. I assume this was with 95 RON (it's now got Optimax in).

I am largely keeping below 5000 rpm, but within that limit I am still doing a fair bit of hard acceleration. There was also some motorway driving at 80-90 mph in 5th and 6th (trying not to keep at constant revs for too long).

I've notived the fuel gauge is very odd - it starts off moving slowly and seems to accelerate as it approaches empty. I think there is lots of fuel left when the warning light comes on.

 

My 1st tank warning light came on at 261, filled up at 275 with 53.5 litres, tank holds 61 litres. @ 23mpg that left me with (7 *.22 = 1.5 gallons = ) 34miles until REALY empty. The way the fuel tanks are setup, I hear, it doesnt do realy empty, it'll stop short.

Depends on how much I/we squeeze into the fuel filler pipe too I guess.

 

Just this minute filled up and thought I would work out the damage.

137.4 miles on 33.86 Litres = 19mpg !!!!!

Car has done 770 miles and yes I have been exploring the top of the rev range.

Forget the consumption, definitely more smiles per mile than any other car I've had.

 

If it makes any difference I have been using Optimax from day one.

Previously in my Alfa I felt that Optimax was giving me an extra 1.5 - 2 mpg.

Haven't tried my 8 on regular fuel yet.

 

How much more per litre is optimax? If it took you from say 19mpg to 20.5mpg that would only be worth it, if it was less than 6p more than premium.

It would also take a number of months of running to gauge such a small mpg difference accurately.

Cheers
---Dave

 

For me , usualy 77-78p pl. ompared to 73ppl for 95.

In my focus , after 3 years of ownership I knew what miles I should get. Optimax got me 10% more, and the car ran far better, for 5-6% more cost.

So far I'm not convinced on it for the 8.

 

Interesting observation Rob. Would be interested to know if the 8 runs better on Optimax.

Just recently tried in my GTi and there felt to be an improvement overall, but may just be auto suggestion.

Why is it that your old car seems to run better than ever just before you replace it???????????

 

Got 19mpg on my first tank. Filled her from the garage at 40miles and ran to 250miles before refilling.

Just hit that 250mile mark yesterday and am running on standard 95ron at the moment. Going to try Optimax when I've gone past 600miles and have started to explore the rest of the rev range.

 

Another update:

I am on tank number seven and I just crossed 1200 miles.
This last tank amounted to 14.8 MPG, which negates the 16.8 MPG of the tank prior.

Still waiting for that magical "ECU Flip". :p

 

Ahem. this tank = 18mpg.

1st 23mpg
2nd 20mpg
3rd 18mpg.

maniac's 6th : 16.8
maniacs 7th: 14.8mpg

I predict by my 10th tank I'll have to fill up between pumps.

 

Indeed.
I expected that my gas mileage wasn't going to be great - it is a sports car, after all.
I wasn't expecting my fuel costs to more than double.
My turbo V6 MX-3 did better than this.
MY 70 DODGE CHALLENGER WITH A 360 AND 3 TWO BARREL CARBS DID BETTER!!!
My company's 1990 full sized Chevy Van with a 305 does better, also.
It is just absurd...

 

Maniac is an American, so multiply his mpg by 1.2 to get the UK equivelent.

Cheers
---Dave

 

I don't see what the issue is with the MPG:

I have a 2 litre Mazda Xedos 6 which is a 144bhp, 172Nm saloon that weighs less than the RX-8 and averages 25 to 27mpg. If guys on here are getting as much as 23MPG with a car like the RX-8 that has 60% more power and 22% more torque (over a wider range) then I think it is a pretty good result.

 

I was getting an average of 26mpg in my MX3 V6, 130hp 118ft/lb (160Nm), also quite a bit lighter. It had to be driven pretty hard as there is a lot around with more power these days, but it could still hold its own. The RX8 doesn't need to be driven anywhere near as hard - but try telling my right foot that

I'm hoping that after a few thousand miles on the clock, I'll manage to keep it on the right side of 20mpg, and anything more will be a bonus.

Cheers
---Dave

 

Only got 17.51mpg out of my first measured tank! Took it steady as well. Maybe she needs a bit more right foot..............

Hope it improves

Cheers
Oilman

 

And on that note, has anybody actually noticed any real difference in fuel consumption depending upon whether they're heavy on the throttle or not?

 

1st tank 1/4 motorway cruse, 3/4 A/B road sprint (within running in).

Rest has been sprint/urban.

Tank1 got me a lot more miles. Either it was the motorway driving, or drive it hard..?

 

Comparing MPG to power torque doesn't really justify it when you consider that I get over 28mpg in my T5 which is 245bhpand about the same torque and weighs a LOT more than the RX8.

All of a sudden I'm concerned about MPG again. A week Friday should tell when I will have gone through at least 3 tanks of petrol! :o

 

It is a concern and anything over 20mpg looks acceptable based on a more spirited drive. Motorway driving in 6th at 60mph will result in a lot more but is it fun.

rael?

 

Mine is getting worse as my right foot seems to weigh twice as much now I'm over 600miles, 18.25mpg on my 3rd full tank.

That was taking it very easy for the last 30 miles with the warning light on. The gauge had been showing completely empty for the last couple of miles, and I managed to get 57.4 litres in. Still would have gone another few, but I wouldn't want to risk it.

Cheers
---Dave

 

Now up to 1700 miles (not bad for eight days) averaging 25.6 miles..... have done about 30% MWay, 40% A&B road and 30% town driving - Am currently quite impressed as I have not been driving like I need a flat cap.

 

I get £0.14 per mile for business petrol (80% of my miles). I have done some calculations - I need £0.18 to break even. Looks like I need to make a case for £0.04 per mile...