Gas mileage question
- Thread starter awmenard
- Start date
I forgot that Canada uses AKI as well. Damn.....
Okay, if you're from the US or Canada - then I'll include AKI.
http://www.torquecars.com/articles/fuel-octane-ratings.php
http://en.wikipedia.org/wiki/Octane_rating
The CX-5 already has extremely high compression (higher than the VW Golf GTI which has a much lower compression but requires 98RON/92AKI).
The experiment I refer to though used detuned cars that were designed for 91RON/87AKI. For these vehicles, the 98RON/92AKI, was still cheaper per kilometre (using Australian pricing at least, which is about 8c more for the 98 versus the 91).
A car manufacture would be in deep dodo if they fudged mileage numbers. The government tests are quite explicit on how the values are achieved. I've observed that people with the poorest mileage are the more spirited drivers and they need to blame someone or something.)Ed
They don't have to fudge the numbers, they just have to tune the car so it performs at its best in the tests. I can look like a genius if I know the 5 questions I'm going to be asked on a test in advance. When you know the exact setup that will be done and the speeds etc you can gear and program the car to be at its most fuel efficient at those times. The farther away people's real world driving gets from that setup then worse the mpg will be.
I always like to look at a good sampling of real world results, throw out the lowest and the highest results and see where the rest land and go off those numbers.
mazdaspd96
Member
Did 7.8L/100 km for a 1000 km trip this week-end... There were a lot of hill on highway should be able to do better... Above 105 km/h the fuel economy is not as good as 98 km/h!!!
Got our best tank yet last weekend. 20% city and 80% highway and got 29.7mpg. Thats with normal driving conditions and not attempting to get good mileage. Running average for 2100 miles is 28.4mpg. The 29.7 was calculated at fill up. The 28.4 is the computer average. Anyone else think the computer is overestimating?
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thegrapeguy
Member
- :
- 2013 Mazda CX5 GT
I have done my calculation at the pump 3 fills and got 28.7, 28.5, and 28.3 mpg. Same gas station, same pump, no extra "top offs". The computer has shown 29mpg. I think it's overestimating but at .5 mpg I'm not ready to call foul play...
What % of your driving is highway/city? I'm getting a GT-AWD in the next few days and am curious to know what my MPG will look like.
thegrapeguy
Member
- :
- 2013 Mazda CX5 GT
I have the GT AWD - I drive what I call "suburban" driving (drive 2 miles hit a stoplight, drive 2 miles hit another) . My computer averages me at about 40 mph. On average I do 20% highway, 20% city and 60% suburban on generally flat roads. My latest tank yielded me 28.93 mpg. This is the best yet for me. I now have about 1600 miles on the car. The last tank included a mostly highway jaunt of about 100 miles. I figure that is the reason I got my best this last tank. The first tanks yielded me as low as 28.3 and as high as 28.7... My computer is saying I'm getting about 29 mpg... All in all for AWD I'm very impressed!
Just reached 2000 miles so I figure I would chime in on this, Im on Fuelly also.
I live in a urban setting and work in a dense suburban town but there I travel highway in between. My daily commute sees about 10-12 stop signs averaging 1/4 mile between them, (15% of miles). 10-15 stop lights with 1/2-2 miles between them in a 40 MPH speed zone, (40% of miles). Finally there's some mileage between home and work, (45% of miles).
It is a very nice 20 minute commute in my 6 speed sport averaging mileage from 26-30 as per fuelly.
If I visit my folks on a 80 highway mile trip I see the mileage average go up and when I drive around my home town racing off of every red light it goes back down. Seems obvious.
When I let my gas tank go down to 1/8th, I can always travel around 400 miles when I put only 12 gallons in.
All in all Im impressed with mileage. Its also very fun to drive and keep those RPMS over 3500 weaving traffic
I live in a urban setting and work in a dense suburban town but there I travel highway in between. My daily commute sees about 10-12 stop signs averaging 1/4 mile between them, (15% of miles). 10-15 stop lights with 1/2-2 miles between them in a 40 MPH speed zone, (40% of miles). Finally there's some mileage between home and work, (45% of miles).
It is a very nice 20 minute commute in my 6 speed sport averaging mileage from 26-30 as per fuelly.
If I visit my folks on a 80 highway mile trip I see the mileage average go up and when I drive around my home town racing off of every red light it goes back down. Seems obvious.
When I let my gas tank go down to 1/8th, I can always travel around 400 miles when I put only 12 gallons in.
All in all Im impressed with mileage. Its also very fun to drive and keep those RPMS over 3500 weaving traffic
Isn't the GTi turbo though? Dynamic compression is what dictates octane requirements.
Yes, about 4% overestimation in first 3000 miles. I'm tracking my mileage on a spreadsheet.
Hold the info button on the streering wheel for a couple of seconds and it will reset.
That's great numbers hollis!, I'm a very aggressive driver both city and highway and I'm averaging at around 34-35. That is incredible. Mazda got it right with the CX-5, I can see this car being the leader in the CUV market real soon.
On the drive home from the dealer - Boise to Redmond, OR, the computer said 34 mpg exactly, but when I filled up and did the calculations, I got 34.9. Either way, I was impressed. I made no attempt to hypermile like I used to with my CRZ. On I-84 out of Boise, the speed limit is 75, so I drove 75. I took Hwy 26 through the Umitilla and the Ochoco National Forests, climbing to over 5000 ft elevation through the passes. When I overtook slower moving vehicles on two lane stretches, I dropped to 3rd gear and didn't waste time getting around them. After a 340 mile drive home, I was convinced that I had made a good decision. What a well engineered vehicle!
