I'm not exactly sure what I'm reading here. Are you suggesting to Redd that there's no way he's getting over 32mpg? 36-37mpg is hardly some wild claim. Outperforming EPA estimates isn't a superhuman task.

 

I agree, I'm not sure why Redd is being attacked. Am I missing something here?

 

Looks like misunderstandings and perceived insults, going back to where the suggestion was to weigh the car before and after fueling, which may be technically possible, but which nobody has the ability or interest to do...

 

Weighing the car is nothing but a horribly inconvenient stunt. Deliberately inaccurate, when you look more closely: do you use a published weight for one gallon or do you weigh a gallon out of the pump and use that number? How are you measuring that gallon, for that matter, and why on Earth do you think one gallon and one partial tank are a big enough sample size to study mileage? It's only useful for a one-off measurement, not a "this is what I get in this car" number.

 

Doesn't bother me, I'm laughing all the way to the bank

 

I just got my car a couple weeks ago, and just went over 1000 miles. So far, with the 3 fill ups I've tracked, I've never gotten under 40 mpg. I've noticed with my other Fit and my Insight, they didn't really start getting good mileage till around 5k miles.

My run today was mostly interstate, 272 miles, and took 6.594 gal to fill back up. In no way a completely accurate measurement of true mileage. But close enough to my now destroyed hybrid, that I'm happy with the decision to not spend the additional 10k to get another one.

 

Very nice. The good news is your mileage will also increase as you continue to learn how to more efficiently drive your Fit.

 

Yeah, a bit different than the hybrid. This things seems to coast forever. On the interstate, I just set the cruise and go. Not the most efficient, but saving my back is more important. Hypermiling for any distance gives me back spasms.

 

When I was heavily into hypermiling, I had 50-60psi in my tires on my old hybrid and that thing rolled forever on LRR tires.

 

This thing seems like a rolling brick to me. Going 65 mph it has gotten one tank at 37 mpg, but going the speed limit of either 70 or 80 this brick is hardly getting over 32 mpg. Driving agressively and 24mpg has been seen once. That was really a let down. I use the cruise control whenever possible mainly to avoid speeding tickets, I have enough of those. lol The only saving grace of the car is that it takes 87 instead of 93 like my other car.

 

The sweet spot for optimal car mileage was always about 55 mph. The faster you go above that the faster your gas consumption increases. That's why the old US speed limit was reduced to 55 mph a long time ago - to optimize fuel consumption.

Mpg For Speed - Fuel Efficiency Vs. Speed

 

I looked at the site and it is one sided for sure. Look at the difference in the drop between the Mercedes and the Opel on the graph of the page you linked to. It is glossed over, but the plots prove my point. I have a different car that has proven to get about 23mpg when the cruise is set to 65 and will get just over 22 when cruising at 95. (it sucks in town, getting an average of 16mpg lol) It's all about the drag coefficient and this car isn't too slippery.

 

The sweet spot for mileage is a combination of powertrain, aerodynamics, weight and driving technique. Huge 70s bricks with big engines, soft tires and automatic transmissons probably had a much lower sweet spot, but guzzlers will guzzle at any speed and people do want to move briskly on the highway, so 55 was about as low as Congress could push for. Once that was established, the factories had an incentive to aim for a sweet spot of 55.

The sweet spot for an underpowered aerodynamic disaster like the Fit... with a manual transmission is closer to 45. Dragging a torque converter along may lower that. It takes a lot of oomph to punch that shape through the air at high speed, and the Fit was last in line when Honda was handing out oomph. It can get there, and it can hang, but it isn't going to get the numbers it's capable of if it spends its day at high load and high rpm.

 

True. Driving at 65 - 70 will give lower MPG. Locally, I'm limited to 55, and with the warm weather, I'm back to averaging mid 40's per gallon. Driving into town, I average over 50 (16 miles, lots of downhill). Coming home, I usually average 45.

 

I'd have to agree too. My sweet spot is definitely in the 40-45 mph range where wind resistance isn't as harmful.

 

I guess this will show my ignorance, but I thought that for a car, the Fit was not an aerodynamic disaster - what makes it so? I thought that its shape (large slanted windshield, flat panels underneath the car), along with a light weight and small engine, helped it get above average mpg.

Aerodynamically, is the GK better or worse than its predecessors?

What are some everyday cars that are comparable to the Fit (sub-compact or compact) that would have better aerodynamics and why? I'm not defending the Fit, I really just want to know so I can learn.

 

10 gallons of fuel does not expand much, I dont think its dangerous to fill within a few inches of the top. But I wouldnt go right up to the top. I work with hundreds of thousands of gallons of fuel and thats when you really notice the expansion when the weather heats up fast. It would cause disasters if you are not prepared for it.

 

I advised her not to fill to the very top, so as not to possibly overwhelm the vapor recovery system in case liquid fuel might get into it.

 

I haven't poked around the GK, but the GE underbody is set up to fail. It's got a huge grille that lets air in and directs it underneath the car. I don't care how smooth it is afterwards, the front end is essentially an air compressor. That's drag that the little 1.5l doesn't need added.

But the front is the least important part of the car's shape; the tail is where the real drag is made. Look at the rear end of a Porsche or a submarine. Then look at the rear end of an 18 wheeler... or a Fit. A tapered rear end gets you much lower drag.

This is not to take anything away from the good engineers at Honda. They were told to make a compact car with lots of useful space, and they did. They were told to make it as efficient as they could, and they did.

I blocked off my lower grille last month halfway through a tank. The three tanks I have with it on are in my top 5 longest tanks ever, and if I'd gone one mile further on that first tank then three of my four longest tanks would have been with the grille block. In April.

 

You can bet that Honda put a lot of time and effort into making this as economical as possible, and a large part of fuel economy is aerodynamics.