I mostly drive to work on a two lane State Highway with a 70 mph speed limit. Late at night, it's often quiet enough for me to pick whatever speed I want (and I've also noticed that a lot of the late night traffic is also going closer to 60, so I think the high gas prices are causing others to drive for higher mileage as well).

But during high traffic periods, it's not really safe to try to go 55 when everyone else is going 75. A string of cars line up behind you, then people get impatient and take stupid chances trying to get around you. The road has just enough curves and blind spots for this to be dangerous - which doesn't stop people from trying it.

Anyway, I'm trying to work out a "medium" cruising speed, that strikes a good balance between mileage and not going too slow and blocking traffic. The tachometer is hovering on both sides of 3000 rpm at various cruising speeds. Obviously, slower is better for mileage. But are there any special rpm's to stay below? At what point does the VTEC kick in, and how much does it affect mileage?

 

Is it AT or MT? GE8 or GD3? The MT's are going to be at a higher rpm than the AT's at the same speed. It's just how thing's are geared. The AT, I'd imagine, gets a little better gas mileage on the highway than the MT does. In my MT GD3, I've gone 65-70mph for a whole trip and still got over 37mpg (which, surprisingly, is only a few mpg better than any of my all city tanks!)

 

I have a 2009, w/manual.

 

The best and safest speed is what the mainstream traffic is doing. If they're doing 75 thats the safest, maybe not the best to avoid a ticket.
If you're by yourself whatever's comfortable just so you don't get a ticket. If they are too risky then its the speed closest to the mainstream that avoids a ticket. In that case its generally the right hand (slowpoke) lane too. And keep a eye on your rear view mirror; some nitwit may decide at speed to pass right and you won't see him coming easily.

 

I would say drive 70mph.

 

Source: US Dept. of Energy

I would say much slower than the previous replies.

 

60 on light throttle pressure is just about it if you want to balance maximizing your fuel economy and keeping a decent pace on your 75-mph freeway IMO

Just keep your eyes open for any drivers that might want to pass you and try their luck on the twisties...and let 'em past. Enjoy the music or something.

 

I personally drive at 70mph most of the time.

75mph MAX if I don't pay attention.

myke

 

I agree that sometimes slower will get you better mileage, but of course as you said, can be dangerous--also may make you impatient.
I say...find a good balance, pay attention and be careful.

Hey you're in Tyler!
I'm not too far away in Gun Barrel City! I visit Tyler frequently...maybe I'll spot you sometime!

 

50mph. **** everyone else on the road

 

Not only is that unsafe, but it's pretty inconsiderate.

myke

 

You'll get a ticket for that in my state, both for violating the freeway minimum speed and obstructing the flow of traffic.

Normally I just set the cruise at 70 and let 'em pass, unless I get a tailwind then I don't feel bad about going 73-74. Still good for about 38 mpg with the AC running.

cojaro is right though, I expected a big difference from my "city" mileage that usually winds up around 35 mpg or so, but that only happens if I can set the cruise at 60 for hours on end on flat road.

 

Which Fit is this, a GD or a GE?

On GDs VTEC kicks in at 3400 RPM.

On GEs, it may not kick in at all at a cruise. The i-VTEC system reads your throttle input; it doesn't activate at a set RPM only unlike previous VTEC systems.

 

jeez with laws like that its no wonder why the US are the Saudi's bitches.

 

On most roads there is no minimum speed, but on our limited-access freeways in Mich the speed limit is 70 for cars, 60 for trucks over a certain GVWR, and 55 mph minimum for everyone. Only rarely does that change, but that's usually in a big city and not for very long.

All other state/county roads are 55 mph speed limit unless otherwise posted.

 

aaaaaaah. got another 52mpg drive home from work! only 46mpg on the way TO work.

 

On 70 mph divided roads and interstates, I usually go about 67 mph. Depending on what I do for the 1-3% in town driving I do, I get around 37 mpg.

 

I find 55mph to be the best, but like everyone has said.. you probably shouldn't be going that slow. It is, however, a good reason to lower the speed limits across the country. We should try and keep them out from under the speeds where wind resistance starts to murder fuel efficiency, ideally, if we're concerned about dependence on foreign oil and the environment. *End Hippy Rant*

 

like type100 said, in the new fits it shouldnt affect mpg that much going fast thanks to iVTEC, on the manual GDs the key is 65-67mph, max speed and just under VTEC engagement i always go this speed unless in REALLY in a hurry or all my passengers are yelling at me

GD owners only: i also periodically get on and off the gas lightly to make sure VTEC hadnt engaged itself

 

I usually drive 80mph when there's no traffic because everyone is going 80mph. If the road is wide open, I'll cruise at 70 if I'm not in a hurry.