Driving "Fast" for 1,200 Miles

Nice!

We often complain about bad mpg when driving fast but what's bad about 42-46mpg? Surely no other car could achieve similar numbers except a handful of diesels.

 

THANKS for posting that! Wife and I are renting a 2011 Prius for a 2000 mile round trip to Yellowstone and wondering what to expect. If the Prius somehow becomes unavailable I'm sure we'll cancel.

 

I took a 900 mile round trip to Dallas, and averaged an honest 75 mph all the way. The 2012 averaged right at 47.5 mpg. My 2005 averaged 38.5 over the exact same route. I'm very happy with that.

These cars are simply remarkable. I have a 2005, 135K miles on it, and other than the $600 I spent at 100K for a general check up, tune up, starter battery replacement ($300!!!) I have only spent 52 cents for a tail light bulb back in 2010.

I really wanted a plug-in, but the timing was simply wrong. Not being in the right state, I would have had to wait another year or two. Oh well, let the other guys find all the flaws before I buy...at least that's what I tell myself as I cry myself to sleep.

On a similar note, my neighbor has a 2011 and he drives an hour to work each day and noted that in the Winter, when he can drive 70-75 mph with no traffic, his mpg averages around 45-47 mpg. Now that Daylight Savings Time is in effect, he can only go 55-65 and is averaging 50 mpg. I find that very interesting. You can get 50 mpg, or better, but you must be willing to back off the throttle! Of course at $4.00 per gallon, closing on $5.00 per gallon, there is an incentive to go a bit slower for another 3 mpg....or is there? Naw!!! I eat the difference and get there quicker!

 

You may want to test that idea. Most people who have timed their commute found that the increased speed made very little difference in total time. It's worth the time to do the math rather than assume.

 

I took the Prius to California last year to go to Six Flags & ran at 5 mph over the posted limit for 2k miles. Speeds ranged from 65-75 mph during the tripIt was hot & I had the AC on all through the night too.
My calculated mpg tanks were as follows....

1. 53.4 mpg - Camas, WA to Corning, CA
2. 47.5 mpg - Corning, CA to Buttonwillow, CA
3. 46.5 mpg - Buttonwillow, CA to Valencia, CA & back north to Santa Nella, CA
4. 43.5 mpg - Santa Nella, CA to Weed, CA
5. 54.9 mpg - Weed, CA to Camas, WA

 

I recently drove from FT Polk, Louisiana to Palm Springs, Ca with about 700LBS (three adults, two babies, luggage) in the car. All tires at 40 PSI AC only sometimes and 5 Mph over speed limit averaged 69 MPH. 3200 miles round trip and averaged 44.5 MPG. Amazing!!

 

My wife and I took our 2010 from Dallas to San Francisco and back. Total miles was over 4300 miles on less then 300 dollars on gas, (this was back in May of 2010) was gone for 17 days. And stayed mostly with in 5 mph of posted speed limit. But from El paso to Midland on I-20, the speed limit is 80, which we drove 90. Running 90 for over almost 2 hours and MPG stayed around 47. We had days were we drove 10 hours with no issue Enjoyed the trip, ready to head to the east coast next.

 

I drove 1150 miles in 181/2 hours yesterday.Started with a tank 1 bar shy of full.Only had to gas up 2 times.I got to drink less coffee and water with so few fuel ups.

 

Interesting, but not at all a surprise, to note that what you consider "fast" is actually average for most european countries. And actually surprised that 75mph are actually legal in some states in the US. "55" used to be the motto a few years back, right?

The average highway speed limit, that I am aware of, in most European countries is 130km/h-80mph (the "advised" speed on german autobahns is actually 75mph; but you can drive as fast as you can, when allowed - as long as you keep safe distance from the cars preceding you - tailgating is strictly not tolerated).

The average fuel consumption I am usually getting at those speeds with winter tires is 43-44MPG. Maybe some diesels can get that, but most cars of same size and HP will actually get no more than 40mpg.

You can read more about driving *really* fast with a Prius (i.e. 90+mph) here.
You can read more about fuel consumption at "fast" EU average speeds with comparison to "fuel efficient" diesels, here.

 

In regard to diesels at highway speed I noticed with
my 2003 Jetta Wagon with a TDI and 5-speed manual
transmission that on highway speed, 65 ++, mpg's
dropped from the low to mid 50's mpg to about
45 - 47 mpgs.

The extra increase from 60 mph to 75 mph
makes a noticable difference in mpg's.

The Prius is fairly consistent at 70 + mph at about
48 mpg calculated and gets better mpg's than my diesel
at high speeds.

 

I would not say that the Jetta Wagon is a masterpiece of aerodynamics...

 

What is the most fuel efficient freeway speed at which to drive a gen 3 Prius? Is it 55 mph or can it be driven faster say 60 or 65 and still get optimal fuel efficiency?

 

Maybe not, but the ALH TDI engine was great for mpg...regardless the chassis the put it on.

 

We just went to Tombstone, AZ, round trip of approx. 3,000 miles. Best I recollect, we averaged 48.6mpg for that mileage. And, we ran 70-75mph most of the way---75-80mph in West Texas and parts of NM. We were happy with that mileage, and about the same for our Colorado trip last summer.

 

In '84, I had a new Nissan Maxima, the speed limit then was 55. I went from Lou Ky to Montgomery Al and drove 55 all the way, averaged 37.24 mpg. Just think what I could get in the Prius at that speed. I was surprised that I didn't get bored at all, I had a book on cassett and listened to it all the way down.

 

No tailgating on the Autobahnen? Was?
My experience driving in northern and middle Germany Autobahnen was quite different . Illegal to pass on the right , so if you are slower than the other cars in the left lane, they will :
1. Tailgate, often to within 2-3 meters
2. Flash headlights at you, with the occassional addition of the horn
3. In extreme and fortunately rare cases, they will close to within touching distance and give you a gentle nudge on the back.
Just wouldn't like to give the Gentle Reader an overly rosy view of the German Autobahn traffic.

 

German tailgating joke:
"What is the difference between a 'traffic-snake', where a long line of cars are backed up behind a slow car in the left lane, and a real snake?"
Answer;
"The real snake has its a$$ at the back end!"

Thus, there is hostility toward left-lane dawdlers , and passing at 130km/Stunde when the oncoming left -lane overtaking traffic is going 220-240 km/Stunde can be very dicey.

 

I enjoyed the heck out of the time I spent driving the Autobahns in both Germany and Italy (and even Great Brittan). I was only able to coax the little Ford Fiesta rental to 135 mph, but it was still exhilarating. I did abide by the "rules", that is to use the left lane to pass only and then move back over. It's really exciting to be going 135 mph, see someone miles back flashing their lights and have them pass you going 175 or so a "very" short time later, can you say "whoosh?" I only remember tailgating though when we entered zones with speed limits and a lot of traffic, and through the l_o_n_g tunnels in Switzerland.