Until I got the Taurus, I coudln't go the speed limit
To go 75 in my truck, would cost me getting 9 MPG! At 60MPH, I got 20 MPG.
Drag increases with the square of the velocity.
The Mustang loves 80MPH but I try not to go that fast. Often, I fail to try very hard. I attribute that to laziness.
On short trips, going fast makes very little difference. I once figured if I went 70MPH, instead of 60, on the highway, to school, I would get there 45 seconds earlier, on the 17 minute drive.
However, If I went 75, all day, I would save an entire day of driving, going across the country. I could drive from my house, in Coeur d'Alene, Idaho, to my parent's house, in Maryland, in 3, 12 hour days. At 55 MPH, at would take me just over 4, 12 hour days.
At the speed limiter, at 145MPH and 4400RPM, I could be there in 17 hours and 15 minutes. But I'd be stopping for fuel every.... goodness, at 8MPG, I'd have to stop more than once an hour. 21 [15 gallon] fill-ups in 17 hours?!?!
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2006 Black, GT, spoiler delete, IUP, five speed, leather, custom welded straight pipes with resonators, Saleen short-shift adapter, sequential turn signals, custom anodized aluminum Longacre ventilated shift sphere. Spydershaft one piece aluminum driveshaft, w/ Spicer 1330 U-joints, Steeda UCA and LCAs. bye bye wheel hop, hello traction! SCT XCalII, BBK CAI.
*I hope to die peacefully, in my sleep, like my grandfather. Not screaming in terror, like his passengers.*
Speed Limit To Be Raised to 70 MPH in Kentucky! 
About time you guys caught up with the rest of the world
Is it more dangerous going 70 in a 60 then it is going 75 in a 65?
