Whats Your Average MPG?
 

So I am from the UK and I get my petrol for £1.30/litre. I purchase £20 worth of petrol that gives me 15.3 litres.. I manage to cover 51 miles for that.. Average of 15mpg.

This car is Killing me when I have a friend with a Renault Megane F1 300bhp getting around 25/30mpg?

What's your MPG?

In the UK do they disclose mpg values for cars? Or do you just buy a car and take your chances?

What other comparisons between you and your friend are making life miserable?

Ken

I get 14-16 miles per gallon in stop-n-go city traffic, I get about 21mpg highway driving.

OP,
Your comparisons, calculations, and units of measure are all over the place, and your sampling range is very limited. If your pumps are in litres, then calculate and compare in those units. And to calculate, FILL the tank, drive until you need to fill it again, reFILL the tank, and use THAT volume of fuel over the distance driven to calculate your consumption rates and comparisons. Sampling your fuel consumption over the course of only 50 miles is not enough for a valid assessment, and calculating fuel consumption based on the fuel gauge or other approximations can be very inaccurate.

I only compare my fuel consumption to what is normal and healthy for the RX-8, as an assessment of its normal running quality and condition. For instance, 16-23 mpg could be considered a normal range of consumption for the RX-8, depending on driving conditions and habits. If you notice the consumption falling lower than your normal range, it could be indicative of an issue that needs attention. It is pointless to compare the fuel consumption of a Wankel rotary-engined car to conventional piston-engined cars, as the designs and dynamics are quite different. Surely, you were informed about this before you decided to buy one, correct?

Yeah, his methodology maybe isn't the very best... But the results certainly aren't atypical. I get 16/22 mpg (city/hwy).

Besides, your friend's Renault Megane F1 is still an ugly Renault. If you must compare your car to his, to base your happiness with your vehicle, at least do a total comparison.

This is a phenomenal point.

16/22 mpg (city/hwy) is pretty much the norm.

My fuel mileage data is in my sig.

If I'd drive only a constant 65 mph on the freeway on flat terrain, I could surely get 24 mpg or above... but what's the fun in going that slow? It'd put me to sleep :)

I average between 18-19 mpg normal mixed driving and 21-22 mpg highway.

OP, You'll probably find more numbers by search the site for this. It's been discussed many times before. I've lost count of how many threads there are on the subject.

FWIW, i don't check mine. I don't even count how many days between fill ups, or how much money i spend when i do fill up.

The average MPG for my 2009 RX-8 since the day I bought it on March 18, 2009 is 19.1 mpg. I drive it to work 85 miles away fairly often in summer, though, so that bumps up my average. When I'm just having fun I tend to get between 12 and 16 mpg.

I average about 22mpg with mixed driving...mainly highway.

10mpg, mostly city.

The cost difference between my 8's mileage and my wife's car's mileage means that I get about 121 miles of fun for the same cost as my wife going to a movie (without going to concessions).

Or about 857 miles for about the same cost as a new pair of her shoes.


I think I'm getting a better bargain.

That is how I am thinking about it as well. It's entertaining and one of my hobbies just like my motorcycle and my bicycles...hobbies cost money. I am new to this car but in the weeks I have had it I seem to be averaging about 15 litres per 100 km.

I had to quote this just because I did a mental calculation when I walked past a pair of my wife's Prada heels in our living room.

I mostly do short drives, so its probably less than it should be.

Mileage
 

I drive 80 miles to work and back 5 days a week. I have a lead foot and go 80 to 90 if traffic permits. I also get in a lot of traffic jams on the way. My son complains that I am "always accelerating".

I get a very consistent 19.5 MPG.

MPG is irrelevant (the way I drive my 8 is 18+ MPG during warmup, 12-15 MPG after) if MPG is important you bought the wrong car. I measure my cars/bikes in SMP (smiles per mile)

Spm*

I agree with blazenblue63. You don't buy a sports car for the gas mileage. On average, I get about 16 mpg city/highway mixed, and I'm alright with that.

When my engine was going south I was getting about 18-19MPG with 50/50 city, highway.

Now with my new engine, I'm averaging mid 19's to 21mpg 50/50 city highway.

Comparing MPG from UK to USA is not relative because the gallons are different sizes not sure the exact size but a UK gallon is just under 5 litres and a USA gallon is about 3.8.
Therefore 25 MPG in the UK is the same as 19 MPG in the UK.
Then the fuel is better Octane rate in the UK at 95 - 100 whereas the USA is 87 - 93.

The same car will get much better MPG in the UK than the USA because of better fuel and bigger gallons.

Not true - different methods in the UK vs. US will result in the octane discrepancy.

The US 91 is roughly equivalent to the UK 95.

Awesome another fuel mpg thread,
Awesome more fuel quality and octane crap.
PPL there are tonnes of threads already on this stuff, really do we another one?


The end is nigh

Mpg
 

Gas mileage isn't irrelevant if you drive 100 miles / day unless you are a kid that only has a car as an expense. I suggest if you only get 16 mpg something is wrong with either your car or your head.

I am really surprised how quick people on here are to slam others. This place must be populated by children.

What happened to being civil? If you don't like a thread, don't read it.

Not slamming on anyone. You know what you get when you buy an RX-8. If you have to drive a 100 miles to work and are worried about mileage, buy a Prius. If you want thrills and smiles you do 16 MPG in an 8.

There's nothing worse than people who buy fun fast exciting cars and drive them like an old fart "saving gas" it's the dumbest thing ever.

So in conclusion. Accept the MPG or trade it in. That simple.

Actually in the UK it is measured by RON(research octane number) on the pump and in the US we have the AKI/PON(anti-knock index/Pump Octane Number, which is the average of RON & MON) number posted on the pumps. MON(motor octane number) is generally around 10-ish points lower than RON but I guess it can vary. The UK does seem to have a bit higher octane but not as high as the numbers would lead you to believe when comparing the two.

Another thing is this car calls for premium, which here is 91 or 93 aki depending where you live. Using anything above that in your car without a reason is not going to help you with anything unless you are going FI or have a reason to reduce possible detonation. The octane rating is only a measurement of the fuels anti-knock properties not the energy it contains or even the amount of octane in the fuel. It is a scale of 0 to 100, 100 being 100% iso-octane(stable fuel) and 0 being heptane(detonates easily) and yes there are fuels above a 100 octane rating but that is because that fuel is more stable or less susceptible to detonation than 100% iso-octane. So a gas rated at 90 octane has the same qualities as 90% iso-octane and 10% heptane.

Was hoping to keep that short but it just seemed everything I added needed another thing to explain it lol.

\


lol I love the comparison between car and wife, made me giggle abit, because it so true. :rollingla Combined city and highway I get about 17.1, at least what my cobb told me when I had one. I think its funny when people complain about poor gas milelage on an rx8, 1 its a rotary it gulps fuel down, 2 its a sports car, gotta pay to play mang.

21-22 hiway, when i'm in texas and can get 93 octane no alcohol, it jumps to 25-27. Go corn growers, another con by our government.

After new plugs - coils - wires - fuel pump and fixing three intake vacuum leaks I get 19.x with around 50/50 city/highway, high RPM every chance I get.

I don't think it gets any better than this; what a great car!

I bought my '05 used and got 11mpg on the first fill up. But I thought it was because I was driving it like I stole it. 2nd tank I drove like a granny and it only improved slightly...

I replaced the plugs/coils/wires & started premixing. Gradually it's gone up to a steady 15.5mpg average. I still drive aggressive and its all city, always in stop & go traffic with about 25+ stop lights between home and any given destination. Sometimes I hate living in CA! :cussing:

I still haven't taken an all highway trip with it yet, so I have no clue how it does on the highway.

rotflmao,

Post 2, brilliant as it is, returns this thread as the top choice.

BTW, 22 mpg, mixed city, back roads and some highway, one carbon burn, 70 miles a day. My 6s did 25 mpg on the same loop.

I get around 19-20mpg in the winter and 22-24mpg in the summer time.

Calculating fuel mileage is the easiest thing in the world. You note how many miles you drove and how much fuel you put in the tank when you fill it completely.
My information is in my signature.

13 gallons when the light comes on is right, that's what I usually see.

You don't normally run the tank dry, and running it dry can damage the (already fragile) fuel pump.

Use Fuelly if you don't want to do the math.

11 MPG is too low unless you are tracking for a good chunk of the tank. My spirited DD with 80+% of city driving usually returns 14 MPG.

Two things come to mind:

- Don't reset the ECU by disconnecting the battery needlessly. It needs to record STFT and LTFT to run the car optimally. Resetting the ECU erases these info.

- Unless you drive a carburated car, there is zero need to warm up the car. At best you are just wasting gas, at worst you can create some other problems. Start the car, wait 15 to 30 seconds, then just drive gently. This applies to any fuel-injected vehicle.