aerodynamics is a fickle science. look at today's F1 racers that use every imaginable trick and dollar to increase the speed of the vehicles with as little fuel consumption as possible. goofy looking things.
for street cars that have to haveuseable cargo space the main factors are the vehicle cross sectional weight, the slipperyness of design and the rear end shape. to get useable cargo with less parts the mpg doesn't allow much room for real consideration. don't get me wrong, the slickness counts but it isn't as big a factor as cross section and rear end.
the fit has a Cd of about .35; the best street car I've heard of is a sedan with about Cd of .30 so the Fit suffers from a flat back end mostly.
we are amused at the claimers of routinely getting 40 mpg when all they do is drive on smooth level roads at steady speeds but think they get really good mpg. Even my BMW 3's can match my Fit purely because their Cd is .32 and my Fit is .35. the amount of work it takes to move a weight from point a to point b is much more dependent on the engine and gearing than anything else
just for an example there is a stretch of road from Hendersonville nc to bat cave that's mostly downhill, some pretty steep that its easy to get in excess of 100 mpg with even some sedans. the ones who matter are the ones that get 32 mpg in regular traffic, up and down highways. the EPA estimates are programmed to simulate that driving. deviating from that programmed drive cycle can get better or worse mpg but unless you compare on the same drive there is nothing to boast about.
I have no doubt that 2 Fit can drive in each other's shadow and unless there is a large weight difference the mpg will be statistically the same.

 

Interesting question. I know two rules of thumb that the Fit violates:

1. Short body
2. Tall

So even though the Fit looks pretty similar from the front and side to our Prius (v)agon, the vagon has a Cd that is almost 20% less.

Mahout: Some examples of 'street' cars that have Cd's much lower than the Fit include the Toyota Prius 0.26, the Chevy Volt (0.28 IIRC), and the Tesla S (0.25 IIRC.)

 

Thank for that piece of info - I was not really thinking about the rear end of the car.
Regarding your grille block, how did you do that? do you have any pics? Any negative side-effects of a grille block?

Which Prius are you referring too?
Is the more boxy Prius C closer to the Fit regarding Cd?

 

I slipped a sheet of corrugated plastic in behind the fascia. Zip tied the top center to a metal bar and duct taped the rest. The problem is overheating- Do not do this unless you've got a ScanGauge or UltraGauge and can watch your temps like a hawk. I spend a lot of time over 200 degrees now, and have to figure out a way to duct some air to the radiator before the weather gets too much warmer.

Here's the pic with it in:
https://www.fitfreak.net/forums/2nd-...ml#post1302571

And a before pic for comparison:
https://www.fitfreak.net/forums/2nd-...ml#post1303033

 

Weather has warmed up here in Tennessee. I have almost 10,000 miles on the Fit so far. I also have the 6 speed manual in my EX. My average since the last fillup with 90% highway and 10 % city is now at 50.2 MPG. This is the first time I have gone over 50 MPG with the Fit. In the winter with cold weather I was at 44 to 45 mpg. Warmer weather lets the gas mileage go on up.

 

Yeah, I love this warm weather. My average MPG is back in the mid 40's.

 

Thank you for the "Do not do this" warning and for the pics.
I think I will start looking more into other hypermiling techniques (simpler ones), and maybe later move into something like this, which would require constant vigilance.

For those who have one, do you like the UltraGauge or ScanGauge better? Any other good gauge options?

 

I don't know what either one goes for now, but the UG was significantly cheaper when I was looking. Better or worse, I don't know- but it's great.

 

Yes, it's amazing what a difference the warm weather makes, having purchased my Fit approx 4 months ago, I am also experiencing the warm weather surge in MPGs and love it.

That would be a tough question for anyone to answer unless they actually used both. From what I've heard, owners of the UG and owners of the SG are equally happy with their purchase. I don't believe you could go wrong with either one, but it's an incredibly helpful instrument, so go get one.

 

I've got an LX CVT and I'm only getting around 35-36/mpg! The highway I drive is hilly and my commute is only 11 miles each way so I don't have a hope in hell of reaching these 40+mpg numbers you guys are reporting! Man, I gotta move out to the Midwest. All that flat land... It would be so wonderful to drive and watch my mpg climb!

 

The worst thing is a stop sign at the bottom of a hill! Doh, I have to lay on the brakes--all that wasted momentum kills the mileage!
On the other hand, stop sign at the top of a hill--coast to a stop without using the brakes. Accelerate down the other side of the hill with little gas, love it!

 

I feel your pain. I can force it to still get 40 mpg with all these hills, but the MT doesn't want me to hypermile, it broke me of my Toyota driving habits.

 

Put a bit over 1k on my EX CVT and have averaged ~38 mpg, mostly freeway miles, but a lot of stop and go into and out of PDX for work...and a good bit of S mode paddle shift back and forth with my co-workers Golf GTI (the little Fit keeps up nicely!)

 

Do you know why many airport codes have X as their third letter? Some airports had only two letters as their abbreviation, so when everyone had to begin using three letters, an X was added to the other two. The airport at Sioux City, IA - SUX.

How would you like to be landing in PEE? Or how about landing in POO? More interesting trivia here -

History of Airport Codes: The Logic Behind Those Three-Letter Codes - ABC News

 

Great trivia to brighten my afternoon. Thanks!

 

Yeah, I seem to give trivia more attention than it deserves.

 

OK, so here it is. I could not find it on the forum so I braved fouled injectors, burned fuel pump, meteor strike while being outside my car with a gas can ect..... The survey says... 12.45 gallons to fill the Fit GK when it is out of gas. 550.0 miles on the tank when it sputtered. Anyway after putting a carefully measured 2.0 gallons in the tank, it still did not register on the fuel gauge. Now I know where to set my new Ultra-Gauge each time I fill up.

 

Thanks for taking one for the team sws. That's really great info to know. So, almost 2 gallons more than advertised, just about the same as my last car which was rated at 14.5gal and I was able to add 16.8gal. Did you fill it completely to the top of the filler tube? And did you remember to subtract the gas you used to drive from the point where you ran out of gas to the gas station?

 

36 deg for my commute this morning. Winter just won't leave us alone. It's amazing how much faster the Fit's average MPGs climb when the temps are in the 70s vs the 30s. This is especially apparent now that we've been teased with a couple of warmer days.

 

Yes, temperature makes all the difference. My last three fill-ups were 41, 44, and 46 MPG.