High Speed MPG

By my math I get about 25-26mpg on average. I've gotten as high as low 30s on road trips and as bad as 20ish assing off a lot.
 
Just drove from NJ to OK last week. Took me about 23 hours total, so if you do the math, I averaged about 67mph. I was doing mostly 70-75mph though. I averaged 30mpg. Most of the ride was up hill. I expect to get a bit better coming back. This car gets much better mileage at 60-65mph. If you feel the need to drive 80mph everywhere, be ready to pay for more gas. Just a fact of life. If you leave your house 10 minutes earlier, you can do 65 and get 35mpg. My S2000 turned 4000+ doing 80. Of course it had an 8,200 RPM redline though. I actually only got about 26-27mpg with that car going that fast.
 
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Depending on where you live, interstate speeds can easily average 80 to 85 mph. Especially in areas where the posted limited is 70. Try going 70 where I live (central florida) and you will be run right off the road.

Believe me I know this, I live in SoCal. I've been on the freeway before with the flow of traffic around 90mph, that doesnt mean you have to follow suit with them in order to stay on the road.
 
19 is the worst I've gotten too, although its getting better as it breaks in. Tromping on it now I get about the same mileage I did babying it when it was green.
Same here. I beat on it a little bit more now that it has 12k miles on it and it seems to retain its gas mileage. Not too bad i guess.
 
i drive from Miami to Michigan 8 times a year. I have done extensive gas consumption experiments, staying behind trucks, etc. the difference between 70-75mph is about 3 mpg i average about 28mpg at 75mph. If I hit 80mph i go down to 25mpg. ive found if i'm not in a hurry and just cruising 70-75 is the best. at 70mph i average 31-32mpg. i bought my car 5 months ago and already have 15,000 miles on it. The trick is staying at 70 and coasting downhill.
 
i drive from Miami to Michigan 8 times a year. I have done extensive gas consumption experiments, staying behind trucks, etc. the difference between 70-75mph is about 3 mpg i average about 28mpg at 75mph. If I hit 80mph i go down to 25mpg. ive found if i'm not in a hurry and just cruising 70-75 is the best. at 70mph i average 31-32mpg. i bought my car 5 months ago and already have 15,000 miles on it. The trick is staying at 70 and coasting downhill.

Wow, I thought I drove alot. I've got a bit over 10k in 4 months.
 
I just did a 400km trip; I will convert to mpg for yas.

I was traveling about 120-130km (80mphish) most of the time. 200km was smooth no passing, but on the way back; I had to pass about 10 times, once at about 220kmph (just had too(lol2)). According the cars computer, I averaged 32mpg the whole trip. I then did a manual calculation and I got 30.2mpg, which is almost bang on to the cars cpu average. (Keep in mind I was doing 80mph most of the way).

PS: Just before that trip (on the same route) I was tired and did not feel like speeding (I know, shoot me...) and I recorded 38mpg. I think my average speed would have been 68-71mph. So it goes to show the difference in driving style for gas mileage.
 
I commute to work about 70 miles roundtrip with about 4 miles around town.
Usually have Cruise Control on at 75-79 with AC on, Computer says 26-30 depending on road grade.

I manually calculated mpg over about 6 fill ups got 24 mpg avg.
I even drove like an asshat one tank romping around town, still averaged 23mpg.

CC at 70 is like 30mpg
I might have been going 95 on cruise control once(still got passed by minivans and lifted trucks) and the computer said 23 mpg(cool)
 
For 100+ mile trips IL to IN, I'm typically doing 75-80 and averaging 26-27mpg (calculated, not the dash monitor), although hopefully my car isn't broken in yet and mileage will be improving (about 4k miles on the odo.) Worst mileage to date however - i reset the mileage meter on the in-dash system and ran an autocross day (11 total runs). Computer said I averaged 5.4 mpg! :D Take that, Al Gore!
 
I had to pass about 10 times, once at about 220kmph (just had too(lol2)).

Yeah had to go at 30km/h shy of the limiter :p ... lol. Though I must say 38mpg on a conservative trip seems waay high.

If I pass traffic regularly, take curves at a good rate but stop at around 75-80mph for the straights I average around 25-27 mpg.

Worst milage for me has been crawling around in city.... I've seen as low as 16 mpg.
 
Look at the air/fuel ratio graph....
Your best mileage is going to happen at anything below 3000 RPM. After that...let the Beast EAT!
 

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I took a trip from Tampa to Orlando this weekend. I had just changed out the dino oil for Mobil 1 & a fresh OEM filter, had 1,050 miles on the clock. Racked up 251 miles on 9.1 gallons of fuel. Just shy of 28mpg. That was 90% highway, and mostly 75-77mph. Frankly, I was slightly shocked that the mileage was that high. But pleased, no doubt.
 
I just did a road trip this weekend and was very surprised to see how well it did on gas as well :)

I left Orlando and drove to gainesville, most of the time I was doing 80 - 85 and lots of bursts up to around 110-115. I figured it would be a sure recipe for crappy mileage, but I achieved 27 mpg! The way back was even better, averaging 80-85 and one burst up to 140 (drive2).... So I guess it gets better with age. I now have 12,000 miles on the car and still loving it.
 
I commute 110 miles round trip on I 94 5 days a week, using the path of least resistance driving style through the Milwaukee Grand Prix (sometimes bumper to bumper for 10 miles) not to exceed 10-40 over speed limit , Silver bullet is 7 months old with Mobil 1 CAI,CBE with 23,723 averaging 28MPG (32 HWY). Time for new tires, try explaining new tires on a 7 month old car to your wife!!!Is that what that noise was in 1st and 2nd?
 

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