i was in the USA Its a straight road the follows the freeway in texas (like 6 hours of nothing till you hit el paso)

I got stopped twice on the way

1st cop stopped me to warn me of the sand that had blown over the road about 10 miles up

2nd stopped me for a warning from going a bit too fast (no ticket)

They stop people mostly just so they don't go insane from the immense boredom, every year I ask them how many people they have seen in the last hour and the answer is always less than 15 lol.

90 mph -100 mph isn't really that fast in modern day cars because they are aerodynamically sound and the suspension can easily handle it.

If you read the Texas driving laws, speed limits are only "suggested" speed limits and gives you a guideline for the road( whether or not you get a ticket for it is completely up to the cop and deeming you unsafe dependent on road condition, how thick the traffic is, and time of day) . People control the speed limit here, if traffic is flowing at 85 mph in a 60 mph its completely legal for you to be doing 85 mph as well. A few places in Dallas, cops will stop you if you are bottle necking the freeway aka going too slow

So way out in BFE where you don't see anyone for long periods of time, you can cruise at higher speeds than indicated and get away with it.

Yeah you can google it if you want and flame me.

I was in a circumstance where i got a ticket for doing 87 in a 70
I fought and won against that tick.
My defense was that: I was on a 4 lane highway and every single lane was doing 85 mph, the cop contested that I was the only one speeding in the left lane. The video tape was reviewed showing that he was cruising at 83 mph- 85 mph with traffic before and after he cited me the ticket WITH the traffic ticket. I simply accelerated a margin faster than the flowing traffic so I could get out of the left most lane so I could make an exit a couple miles up the road without obstructing traffic in the PASSING lane by braking and slowing down two lanes so I could fit in (In texas the left lane is considered a passing lane)

He simply singled me out for having a brand new sports car and being young.

To add onto that, some of the mid night rallys I attend consist of about 50+ cars going down deserted freeways getting across the dallas-ft worth metroplex at cursing at speeds close 100mph. We go by cops and they just sit there, we had one of them follow us to our destination and told us to just watch out for other motorists (mind that during the 5 miles he followed us we didn't pass a soul that wasn't with us. And mind that there is a difference between racing, trying to top your car out, and cruising at 80mph - 100mph.

btw the FR-S AT gets about 26-28mpg cruising at 90mph

Also there is a road in texas that's 85mph, I've traveled on it a few times and have seen traffic cruising at 100mph and the cops don't do anything to to those people either.

Faster is safer when outside of large cities, the autobahn has proven this year after year. The most deadly accidents usually involve 2 or more cars, and when you don't impose a speed limit, people tend to spread them selves out and put larger distances between each other. If i ever drive faster than the posted speed limit, it's because I can visibly see a break in traffic and I can get away from the other people on the road that are on their cell phones not paying attention.

What's more dangerous, a person traveling 15mph faster than you in the left lane with clear road ahead of him. Or someone traveling 10mph slower than you merging into your lane?

Im sorry i drug this post out but i realized that what i posted could have easily derailed this thread. Any response to this post not relating to the OP, I will not acknowledge. EDIT: I'm not directing this specifically towards @humfrz I'm just saying that I don't want anyone trying to internet police me. 99% of the time I just flow with traffic getting from A to B.

So to get back on track

I drive an auto FR-S

55 mph 45 mpgs
60 mph 43 mpgs
70 mph 39 mpgs
75 mph 37 mpgs
80 mph 36 mpgs

These are rounded amounts, amount can be higher because the numbers i have seen are not on flat roads and do see some slowing and acceleration and very light elevation changes

Number that I have posted are long distance numbers, If you are diving within the city's limits on the freeway you probably won't get these numbers due to the constantly fluctuating flow of traffic.

I haven't done much long distance traveling at 85 mph+ from full to empty without stops because it hurts gas mileage too much where in the celica it didn't affect gas mileage. I can tell you it is less than 30 mpgs above 85mph in the FR-S, the money saved by going slower than 85 mph on long trips is enough to buy me a nice steak dinner when I reach my destination. I would much rather have my steak dinner, than to get there 15% faster after a 10 hour drive.

As a side note, I get pulled over every time I go down that back road highway and never get a ticket. Simply put, they average speed that people drive down that is the better half of 80 mph. Just don't get caught trying to chase your car's top speed. The only people they pull over and ticket are the people who have headlight(s) or taillight(s) out, the people doing well over 100 mph, or people passing recklessly and not giving common curtsy to other motorists while over the speed limit.

According to the owner's manual (Section 5.2, Page 365):

Yes, given "summer blend" gas and favorable winds. Headwinds will chop your MPG impressively.

Summer/Winter blend of gasses can affect MPG as well. My driving habits in winter are different than in summer anyways. I'm seeing 27-30 MPG during winter and 29-32 mpg during the warmer months.

Very possible my current average MPG is 32

Ahhhh......yes, so it was in Texas, USA ......:thanks:

I like to improve gas milage whenever I have the chance, just to see how well this little car can do it. I usually set the cruise control at about 72 on the interstate and even if the computer starts at around 27mpg (averaged over 150 previous miles) I can increase it to over 30 (averaged over 300 total miles). The actual math turns out to be about 29.3 or so. Now imagine filling up before such a trip. A while back I did a two hour + drive with cruise set to right around 70 and the computer said 36, I calculated 34 at fill up.

Nope I can get close @28 but not really any higher.

Then again I cant say I truly get a full tank of highway driving either so there is usually around 50/50 mix of city/highway driving.

Technically, no, it isn't. Exponential means that it is of the form k^x, where k is some constant. Quadratic is a special case of polynomial, which is of the form k0 + k1*x + k2*x^2+k3*x^3+...+kn*x^n (where k0, k1, k2... are constants). Exponentials grow much faster than polynomials (in the limit as x --> inf), which is why I said quadratic drag is quite a bit better than if it were to increase exponentially.

http://www.knewance.com/comparisons/...ic-growth.html
http://www.math.ucla.edu/~bnelson6/E...ial_Growth.pdf

(and as I said before, I know I'm being pedantic, but I can't help it on technical topics, since I'm an engineer...)

absolutely, but im in A/T.

I got ~33 mpg on my trip from CO to OH going for the majority of the trip 75mph.

Ah, I blew those lectures off when getting my degree. You seem to be correct.

Just because you sat in classes for four years doesn't mean you have to correct everyone, you never know how educated your opposition is.

:cheers:

No offense intended, just trying to use terminology correctly. Cheers!
:cheers:

that isn't bad considering the elevation changes

MT or AT?

30mpg while driving a constant 75mph... id be surprised if you couldn't get 33mpg...

my last tank I got 27mpg according to fuelly and it included 70 miles of city driving, and 5 1/4 mile passes. And I drive at around 80ish on the freeway

Yeah, overall downhill. ;)

Yes I live off I-30 about 65 miles from office right off I-30 as well. I always go 10% over limit cant go on record if 10% or > over limit in TX going 80 usually on cruise get about 32.1 manual calculation the computer says just a few over usually like 32.4

You can hit 34+ MPG fairly easily if you travel constantly in the 50-60 mph zone for an extended time. Not that anyone would wanna do that in this car.. But I went through over an hour on some rural roads (35, 45, & 55 mph speed zones) coming back from outta town to a friend's house, and even with some stop lights/signs, I averaged mid 30's every time I make that trip.

I get 32.8 as shown on the computer on my day to day commute which is 20% city and 80% highway @70mph. The actual MPG at fill up is really 30.1-31.1.

For road trips we have gotten as low as 32.5MPG and as high as 40MPG with an insane tail wind. I am at 15K right now and have noticed that the MPG is improving as the car breaks in.

A manual, overall its downhill after passing through just a bit of Kansas heading east. There were lots of hills though for sure. The funny part is the elevation actually goes up a bit more from Denver heading into Limon CO. Once I got closer to Ohio it was more like 31.5 mpg (But I did throw a bit of fun in there once I broke it in:)). The car was also fully loaded. Four tires, baggage for two, stuff I was bringing to my place in OH, etc.

yeah its hard for me to go on long trips without opening the car up once or twice lol :P and every time i pass a dirt road that looks like it goes off to no where it doesnt help either because dirt roads + rwd is heaven

Not too long after getting the FR-S I took a road trip where I knew I was able to fill-up, hit the highway, and calculate my average speed based on mileage and time. These were the results (documented here, along with what happens when you use the FR-S as a soapbox derby car):

08/14/2012: 270.50 Miles, 33.08MPG Highway Calculated Avg Speed 72.4 MPH
08/16/2012: 276.50 Miles, 31.60MPG Highway Calculated Avg Speed 73.2 MPH


I later took a similar trip on a different (less elevation change) road and got this, although I didn't calculate the average speed as precisely. This trip (documented here) included 45 minutes of bumper to bumper traffic as well:

12/14/2012: 395.20 Miles, 35.60MPG Highway Speeds (70+MPH)

It's generally accepted that drag increases with the square of the speed. For the purposes of the discussion, the result is the same: lots more gas to go a little faster.

On average, with mixed driving I'm getting ~31mpg manually calculated. I cruise at 80-85 on the highway too

Yes it does - and drag being proportional to the square of the speed means that it is quadratic, not exponential. That's what I was getting at there. Also, with cars, you have to balance a number of additional factors - rolling resistance is approximately constant at all speeds for example. This means that the total resistance acting against a car's motion is nearly constant at low speeds, and starts to increase dramatically at high speeds (which is why crawling along at 15mph isn't necessarily the best for gas mileage). You also have to balance all of this against the engine's efficiency curve - lugging the engine at 30mph might cause you to get worse gas mileage than cruising along at 55mph at 2500rpm for example. Nearly all modern cars do exhibit a sharp falloff in efficiency above 70mph or so, though, simply because they're designed with that kind of cruising speed in mind, and as such, the aerodynamics, rolling resistance, engine efficiency curve, and gearing is designed around cruising efficiently at 50-65mph.

(as I said in the last post, sorry about the pedantry, but I'm an engineer with a masters degree in fluid dynamics, so I tend to be picky about these kinds of subjects)

I don't know if your fuel is worse or what over there, but here I have managed to average about 44mpg (5.3L/100km).
I thought it was 5.7 but I found my paperwork from my experiment.
2012 6AT GTS, stock condition.

Now that I have modified my car, I am only getting 34.9mpg with 18x9.5 wheels.

But driving like that is boring.

I live in AZ... I am currently driving at 28.1 city on avg when I burnt a full tank on just hwy driving I was at 34.6 mpg. Avg speed was cruise control set at 75

Drove to Virginia Beach 2 weeks ago and got 31.69 mpg and probably ran around 70 most of the way.

Im still break in period about 700 miles.. I get 28mpg highway... Automatic.. Is that normal? :\
Driving 80/20 Highway/City

Speaking of the trip computer, how accurate is that thing? When I use average it seems pegged at 25mpg even with I granny drive or try to hypermile..

I can get the mpg up in the 40's if I stick it in 6th and cruise at about 45mph.

My overall average right now is 27mpg combined with my commute being about 50% highway, 50% backroads and frequent start/stop conditions. I'll take it considering my Audi gets 15mpg doing the same commute :thumbdown: (granted it weighs 1,200lbs more and makes 2.5x the horsepower and torque)

Yes, about a month ago I took a trip from San Jose > Los Angeles and was going an average of 75-80 mph, got 32 MPG.

You might want to reset it from time to time, in case aren't. I often forget to reset mine but I don't use it that often either.

I just got my new car a few days ago so I have only been driving it occasionally (Haven't killed the free tank of gas yet), but I noticed that my mpg is hitting closer to low 20s yet I keep my rpms pretty low . I know there can be many factors but would you say your gas efficiency improves after the car engine has broken in ? I have never owned a car since single digits on the mileage so I don't have any prior experiences , any thoughts ?