Gas Miles per Gallon tracking

[Karl Roth]

Originally Posted by carolthompson323

Thanks, Smart Card. I see you have a Cabrio -- I ordered one also but I'm thinking of getting the Passion coupe with moonroof (but only if the moonroof opens)!

It does not, if you need the roof to open go with the cabrio

[carolthompson323]

You answered my question. The cabrio it must be!

[gamernotwatcher]

So here it is, I live on a hill 70 yds up from the stop sign to home, its best to shift to manual or else it doesn't like to leave 1st gear, slurp. If you do not drive 70 miles+/hour through camp pendleton, or for that fact any where in Orange County, you are a traffic inpediment/hazard. I would say for the last 10 fill ups average trip length is 15 miles. 80% freeway. I try not to use a lead foot on accelerating, knowing I won't win.
The 36mi/gal tank I thought I was trying to stay within 65mph range. There are anumber of times that I am going up and over the city, looking at a 1000 ft elevation gain and loss 30mph. Over all, I want this car in the 40's.
We use Costco Gas usually, but am willing to test Chevron and/or Shell, or Mobil. Any preferences arise out there yet?
Has anyone had any satisfaction from taking it in to the dealer, for looksee?
Does the K&N air filter make a difference?
I am keeping meticulous mileage record in a small notebook recorded below are the 23 fill ups. Thanks ahead for others feedback
Gallons Miles/Gal
8.1,,,,, 28.1
4.43 ,,,, 32.7
7.214 ,,,, 32.7
6.223,,,, 33.12
7.3 ,,,, 35.52
8.3 ,,,, 34.08
2.3 ,,,, 41.4
4 ,,,, 36.4
5.3,,,, 33.76
7.8 ,,,, 34.08
5.4 ,,,, 34.4
7.67 ,,,, 37.1
5.219 ,,,, 36.73
7.873 ,,,, 36.19
7.591 ,,,, 36.7
7.089,,,, 33.46
5.6 ,,,, 32.09
4.568 ,,,, 34.39
8.45 ,,,,35.32
7.090,,,, 36.56
6.6685 ,,,, 37.04
7.902 ,,,, 36.43
8.791,,,, 38.23

[WhiteNBlack08]

I'll answer your questions with my own personal experience. Yes the gas does make a difference. I find that my smart does get better gas mileage using either Shell or Marathon gas. You can read about it on other threads, but try to avoid gas with 10% alcohol. Yes the K&N air filter does make a difference. I had to fill up today, and recorded my best mileage yet 45.3 mpg. 394.4 miles, 8.7 gallons(yes I cut it close). Also, my experience shows that anything over 60mph begins to really affect mileage. I've made 3 trips back to the dealer 125 mi each way, interstate all the way, my mileage dropped to 36.

[geosynch]

In my Cabriolet I typically get 35 MPG and have never gotten higher than 38 MPG. As such, I have been envious of the 45+ mileage I have seen reported here and elsewhere.

As an engineer, I studied aerodynamics in school 20 odd years ago. (But my work experience is in spacecraft.) So it was obvious to me that driving with the top down is going to increase drag and decrease gas miles. But 22%? I was surprised, especially since most of my driving is on surface streets at 45 MPH or less where aerodynamic drag isn’t as much of a factor as it would be on the freeway. (Aerodynamic drag goes up with the square of velocity.)

And it is genetically impossible for me to drive with the top up. Unless it is raining. Which it rarely does here in the SF Bay Area.

So, I performed an experiment to quantify the effects of top down driving. Here is the set up:

• A 24.9 mile circuitous route around San Jose, CA (85S -> 280S -> 880N -> 101N -> 237W -> 85S) which is multi-lane interstate for the entire circuit
• Scangauge to measure MPG
• One smart Cabriolet, with the a/c off
• A beautiful California day in the mid 70s with a moderate breeze off the bay

I chose a circuitous route to minimize the effects of wind and elevation rise (this route is not hilly at all, but it isn’t billiard table flat, either).

I first drove this with the top all the way down, side bars removed and windows down. The result was 45.2 MPG. I then pulled over, put the side bars in, put the top up, rolled up the windows and drove the entire route again and got 49.3 MPG. I was successful in maintaining a constant 60-65 MPH for both runs (with the exception of two ramps that must be negotiated at about 30 MPH). I also did my best to drive with a light foot the entire time.

So, at freeway speeds, it costs about an 8% decrease in mileage to put the top down.

Since I got my Scangauge I have determined why I get 35 MPG. About 90% of my driving is my 3.8 mile commute to work. In those 3.8 miles I have 11 stop lights, some of which can be long. Sitting at a stop light I can see my 40+ MPG average integrate down to less than 35, depending on when I reset the gauge. So while I can get 45+ MPG on the freeway, I have never got better than about 35 MPG on my commute to work, and that is with a very light foot.

And driving with a light foot is something else that is genetically impossible for me to do.

geosynch

[tbranca]

geosynch
I think you hit it on the head.

[c20500]

I finally had a chance to take a hwy only drive to maximize mpg. I drove 98 miles on a topped off tank and it only took 1.9 gallons (91 octane) to top off again! All driven under 70mph and I drafted a semi for 30 minutes following arpx 35 feet behind. close to 52 MPG!, On the way back, there was a stiff head wind and I drove with no regard to economy, and no drafting (80mph sometimes) and got only 32mpg...

So if driven carefully it is possible to get 50+ mpg but it is a bit impractical to do as it's difficult to not get run off the road going only 65 on most California hwys.

I also drive it to the Rock store in malibu and on the way (mulholland Drive/hwy there are fotog's snapping away and while they take mostly motorcycles, here's my shot.

_SPH0085 on Flickr - Photo Sharing!

Charles
Redondo Beach, cA
silver/black passion coupe'

[zman88]

I've gotten a low of 42mpg, using a lot of A/C and a high of 56 just recently, by using the P&G technique, shifting into N and/or shutting things down on downhill glides where I could see an upcoming red light. No drafting or any of that nonsense-too unsafe.
This is over all types of terrain and roads, but it seems to do it's best OFF of the interstates.

[NCC1701]

Originally Posted by Fredvon4

When you start posting MPGs on these things please add:

Location:
Typical terrain: (hilly, steep mountain, sea level, altitude etc..)
Driving style: (hyper-miller, lead foot, sporty, conservative etc..)
Load: (single drive mostly, driver and passenger mostly etc..)
Fuel brand and octane: ( Shell, Chevron, 89, 91, 93)
Clean air blend: if any (10%, 15% ethanol or MTBE)
Total tank fulls in the average
Tire pressure: (please check this cold as it makes a significant difference in performance and seriously effects MPGs)

Panama City, Florida
Flat, small hills, mostly within 20' of sea level
Lead foot/Sporty
Mostly drive alone
Chevron 93 Octane
No Ethanol
Six gasoline purchases, totaling 39.336 gallons
Mileage at last purchase was 1,322 = 33.61 MPG
Checked tire pressure after purchase: All four were down several pounds. I adjusted them to correct pressure 23 days earlier and again today.

[c20500]

I wanted to see if max tire pressure would be a bit much on the car and it's not that bad.Sure it's harsh but not much worse than what it was with 32psi set at the dealer