If driving on the interstate at 60, 70, or 80 mph, how close (in feet) do I need to be to the car in front of me to get the mpg savings?

 

Serious. You do not draft period. It is called tailgating. If you were behind me you would not have time to stop when I touch my brakes.

 

Agreed. If you're close enough to have a mileage benefit, you're too close to be safe. You can be safe, OR you can gain mileage by drafting, but not both. You can't see what's in front of the truck. You can't see the blown tire or rock or 2x4 or whatever it is they're about to throw up in your face.

I did a test once in my Odyssey. 70 mph and drafting 2 secs behind a truck was the same mileage as driving solo at 65 mph. Just slow down a little if you want to save gas.

 

Oh. I have seen other people on various threads say one way to increase MPHwas to allow someone in front of you break the air so you don't have to.

I was thinking at those speeds one could accomplish this at a safe distancesince the post in the other threads weren't challenged. I wasn't intending toget right up on someone.

 

Just tuck in between two trucks, you don't even need to be that close to the one in front of you for it to work.

Note: This is best done on long open interstates cross country where truckers are going 70-80mph, not in town. Also, you may become a sandwich and die.

Don't draft, don't tailgate.

 

Mythbusters tested it. I think they started noticing a difference at 40 ft.

 

Sure and if you're real sneaky you can ride up in his blindspot, start to overtake and just creep in front to rest on the brush guard so he can push you in neutral.

 

Bam!



Dangerous as hell, not worth it for a few extra MPG's especially since drafting a big truck or bus can result in them kicking a rock and cracking your windshield

 

Oh yeah, wasn't it a dodge magnum too? I was impressed with the mileage and kinda grumpy that my CRV at the time was maxing pout at 27/8

 

So if at 100 ft at 55mph saved 11% then if I'm going 80 and I'm 120 or so feet away that should save around 10% and it's a safe distance. Of course I extrapolated their data but it does seem like you can do both....be safe and save mph.

 

If you think you can react at 80mph and get stopped in 120 ft go right ahead. One less idiot on the road.

 

If you're just reacting to the truck you should be fine, a Fit will definitely outbrake a truck (I hope anyway lol). Clarification required

 

Much of it is reaction time. And that's a truck stepping on his brakes. What if what slows him down is he hits another truck in front of him? Then you're toast.

 

Or this. 2x4 through the windshield.

 

120 feet at 80 MPH is a one second following distance. That's not safe. (Some people may drive like that, but some people do all sorts of unsafe things.)

 

"Safe" following distance at 80mph is over 300ft for reference OP, just keep that in mind. I know 100 feet sounds like a lot but it's not at 80mph. I am mostly playing DA here.

 

Don't draft. Is your body or life, or your Fit, worth the few extra dollars you might save during a road trip?

Our Fits already achieve 35-40MPG highway so there's no need to tailgate a larger vehicle. Any gains are negligible compared to the probable detriment.

Read Waizzz' post about the MythBusters test:
If you're trying to save MPG on a road trip then just drive a little slower, be smooth on the throttle, and always use the correct gear. And remember the "2-second rule" about following distance.

 

On I-5 recently through Central CA I was getting 39mpg driving solo at 65mph (as slow as I felt comfortable given the 70mph speed limit) and 50mpg at a ~1-1.5s following distance at 60mph behind a truck. AT 2010 Sport fwiw.

I'd agree it's more dangerous than driving solo, but if you look at anyone following a truck in a passing lane (i.e. whenever a truck tries to pass on a 2-lane highway), they're way closer than 1s.

 

Stay home OP! Best gas-saver!

 

Who cares about the instant readout on your gauge cluster? Full tank numbers or no numbers man.

That said, I got 45 mpg from Madison, WI into the Chicago loop and back, WITHOUT drafting at all.

That includes driving in stop/go traffic for 1 hour and traveling a total of 8 miles.