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Some advocates are calling for the American driving public to take its collective foot off the gas (http://features.csmonitor.com/environment/2008/06/10/can-you-drive-55/)

http://www.cleanmpg.com/photos/data/506/DWL.JPGEoin O'Carroll - Christian Science Monitor - June 10, 2008


A calm, sensible approach to slowing down. -- Ed.

With the national average gas price breaking $4 a gallon and looming fears of peak oil and catastrophic climate change, some advocates are calling for the American driving public to take its collective foot off the gas.

Shortly before Memorial Day weekend, the Sierra Club exhorted drivers to slow down with its I Can Drive 55 pledge to obey the speed limit. There’s also drive55.org, a site launched in 2002 by ecopreneur Tim Castleman that has been getting more attention lately. Mr. Castleman’s site includes statistics indicating that easing up on the gas saves money, the planet, and lives. His site also sells bumper stickers with messages ranging from “55 for peace” and “55: support the troops.”

Why does driving more slowly save gas? It’s a matter of drag. Your wind resistance increases as a square of your speed. So at 80 miles per hour, the wind resistance is more than twice what it would be at 55 miles per hour, because 80 squared (6,400) is more than twice 55 squared (3,025). But at 80, you’re only traveling 45 percent faster than you are at 55. … http://features.csmonitor.com/environment/2008/06/10/can-you-drive-55/

Nice find Laurie

I'm too important :rolleyes:

I like 55mph. I wish more folks did! H

When I first got my license, the limit was 55, and people drove 65. They moved it to 65 and people drive 75 and in some places the limits are 75...

I can absolutely drive 55 (would like still do between 55 and 60) but I wouldn't be as much of an obstacle to the speeders doing 65! If they wan't people to drive 65 drop the speed limit to 55 again! LOL...

Since I am facing the prospect of paying for car insurance for my three boys when they become teenagers, you can bet that I am teaching by example when it comes to driving 55.

I had a 1988 CRX HF as the nation was letting go of the 55mph speed limit. It did not quite sink in my FE was partially impacted from going faster (conditions of the car the other :o )

Personally, and I take a lot of flack for this, I am all for bringing back the National Maximum Speed Law (http://en.wikipedia.org/wiki/National_Maximum_Speed_Law) of 55 mph.

I suppose I'm in the minority on this site, but I'd rather not see 55 everywhere. It's fine for highways within metropolitan areas, but I'd prefer 65 or even 60 on rural freeways. I suspect there are a number of vehicles that actually run more efficiently in steady-state cruising at 60 vs. 55 (though admittedly, they're probably still in the minority).

Anyway, my mom was pleased to get 43 mpg out of her '97 Saturn SL1 when she drove from SE Minnesota up to Fargo recently. She simply dropped her speed down to 65 (most of the way on I-94 is signed at 70).

Changing the speed limit will not have a positive effect until people have iFCD's in their cars.

I'd rather see an iFCD in every car.

I'd be all for 60 or 65 (or 62.5 = 100 km/hr!) but I think 55 is too low. 55 generated a huge backlash. Might seem reasonable back east, but west of the 100th meridian you'll have a firestorm on your hands.

I'd be all for 60 or 65 (or 62.5 = 100 km/hr!) but I think 55 is too low. 55 generated a huge backlash. Might seem reasonable back east, but west of the 100th meridian you'll have a firestorm on your hands.

I have to agree, instead of forcing people to drive 55 we should enjoy the fact that driving under the speed limit is legal. Let's keep spreading the word, even if people simply slowed down to the posted speed limit a lot of fuel would be saved. As it is now, the posted speed limits are nothing but a suggestion. Baby steps........

Changing the speed limit will not have a positive effect until people have iFCD's in their cars.

I'd rather see an iFCD in every car.Brings back an old idea - get California to require new cars to have an iFCD and trip mpg on the dash...that will spread to the rest of the US and encourage some drivers to rethink gunning the car.

We do not need a change in the speed limit. What we need is for it to become socially unacceptable to speed. Somehow breaking the law by speeding is no big deal to the majority of people and often not enforced.

We all know of selective towns in our area of the country that people warn you about when it comes to getting a speeding ticket. "Hey, be careful and don't speed in XYZtown, they really look for speeders."

Now, what if a whole state became known for this? A social marketing campaign to change peoples attitude about speeding. I personally would like that. Here's my slogan:" In Wisconsin, the Speed Limit Means the Speed Limit". You could have a whole campaign with billboard, education components, etc based around it.

And if this spread nationally that would be great.

There is no need to change the speed limits. Let's work with what we already have instead.

edited: I also like DF's idea of making fuel consumption displays a requirement.

Eric, I think you're right that we need to bring back enforcement.

You do have to keep an eye out for the potential for selective enforcement though. Having grown up <10 miles from Wisconsin and often had to travel across the state to visit relatives, I well remember the days when 56 mph on I-94 meant you got nailed.

What sucked about that is that if you were from out of state (1) you were a lot more likely to get pulled over and (2) you went to jail if you didn't have enough money on you to pay the ticket on the spot. IIRC, (2) only applied to out of state residents, which I thought was ridiculous.

If the limit were dropped back to down to 55 I'd have a big problem with that, and I'd hope for the 5mph grace that most jurisdictions outside Wisconsin recognized. OTOH, if the limit remained at 70 I would have a lot less of a problem with it.

It's fairly easy to drive 55 in the right lane in El Paso...when in my car. It's too dangerous to go much below 70 on the motorcycle.

Hi All,

I think slowing the trucks down to 55, which what the truck speed limit was when I learned to drive - just before the oil embargo - akes allot of sense. At that time cars had a speed limit of 70 mph. Slower trucks will limit the speeds of allot of traffic. I think this would mean that the two right lanes in 3 and 4 lane interstates would be doing 55 mph all the time during rush hour, when traffic is flowing.

And trucks seem to be the vehicles most resistant to aerodynamic improvement. So a whole bunch of fuel is saved. On a competitiveness point, trucks wont slow down to 55, unless they all have to slow down to 55.

Maybe one way would be a .25 Cd certification for trucks. Trucks above .25 have to do 55, and below can do the car speed limit. This would have to include the trailers too. Which is why i suggest this. Right now the customer typically owns the trailer, and could care less about the gas. But if the trailer was not certified to .25 Cd compliant, there would be a mandatory up charge on the set value of the freight moving service, besides the adder per pound.

In a perfect world 55 would be fine, but this is Texas. Texas Hill Country, more specifically. If I want to go 55 (average), then I must at times find myself going 70. Gliding downhill, of course, just so I can make it up the next hill.

EDIT: I sometimes get behind someone bent on never exceeding 55. I cuss their stupidity, throwing away all that downhill momentum. Wonder, what do they have to do, get a brake job once every year?

Just made this a poll question...low/no tolerance for speeders might do more good than changing the national speed limit to 55. Over the years, drivers have been given more and more leeway.

I'd be all for 60 or 65 (or 62.5 = 100 km/hr!) but I think 55 is too low. 55 generated a huge backlash. Might seem reasonable back east, but west of the 100th meridian you'll have a firestorm on your hands.
No lie. At 55 out west you can drive forever and get nowhere...
Now, the 80 mph out in west Texas, IIRC, may be a bit excessive.

I think a iFCD on the outside of the car where a cop can see it, and then regulate fuel consumption instead of some arbitrary speed like 55, then you'd maybe have something useful. Or have the car broadcast fuel consumption via RFID technology or something similar...

EDIT: There ya go... If you can show you're getting 50MPG+ go as fast as you want out in the near endless desert. :woot:

As it is now, the posted speed limits are nothing but a suggestion.

I was coming home from CT on I95 a couple of weeks ago and was shocked to see a sign that said Maximum speed 65 Minimum speed 55!!!!!!! So I was breaking the law everytime I slowed climbing a hill or put my mpg right into the toilet (replace word with slang).

wow, that's hard core.

I was coming home from CT on I95 a couple of weeks ago and was shocked to see a sign that said Maximum speed 65 Minimum speed 55!!!!!!! So I was breaking the law everytime I slowed climbing a hill or put my mpg right into the toilet (replace word with slang).
Where was that sign? There is a sign on the southbound side just past exit 64 that says Max 65, Min 40. I haven't noticed any other minimum signs between there and New Haven so I assumed that applied over that whole section?

I don't know if I could drive 55. I'd have to speed up. How do I indicate that in the poll?

I sorry, but I am still for lowering the speed limit nationally. There are far too many states that allow 70-80 mph and we all know that it is so hard on mpg and survivability of accidents. Most of us want to reduce our dependency on foreign oil, but the minute someone says lower the speed limit everyone has a reason to keep it up high. Lets take it down to at least 65 & have no tolerance for obvious speeding.

A bit of both. I say a national maximum of 70 or the states lose highway funding. The bigger, more open states especially out west would drive a man insane if he couldn't go above 55 for thousands of miles.


But I would seriously crack down on speeders and tailgaters. It's a speed limit, not a speed requirement. The rest of the country should take a hint from the Ohio Highway Patrol.

Where was that sign? There is a sign on the southbound side just past exit 64 that says Max 65, Min 40. I haven't noticed any other minimum signs between there and New Haven so I assumed that applied over that whole section?

I don't know if I could drive 55. I'd have to speed up. How do I indicate that in the poll?

I think it was in RI., but can't be sure. It was northbound. Only reason I remember is that I have never seen one with a 55 minimum before - ever!

To use 6th gear in my motorcycle, I need to do around 70 mph, to avoid lugging the engine. I still get 45 mpg or better at that speed. That's more than twice the average fuel economy of the typical American FSP.

Harry

I think a new speed limit would be much easier than rigid enforcement. There just are not enough cops to patrol every stretch of road and using traffic cams or other methods would probably send the ACLU into cavalry mode.

Just made this a poll question...low/no tolerance for speeders might do more good than changing the national speed limit to 55. Over the years, drivers have been given more and more leeway.Why does this have to be an all-or-nothing choice? Seems like much of the discussion continues to focus on 55 as some magic number that we would go to if we reimposed a national speed limit. There's nothing magical about 55. If there is any magic number it's either 60 mph (mile-a-minute) or 62.5 (100 km/hr).

Most states allow 70 mph right now, and many (including all inland western states) allow 75. Even a 65 mph national limit would save a lot of fuel without generating a backlash. 60 would save even more without being too draconian, would still allow a mile-a-minute pace, and would allow us hypermilers to avoid getting ticketed for speeding on every downhill stretch.

55 MPH is a good speed for conserving gas, and that's what we need right now.

The stupid 80% rule for traffic speeds needs to be exposed for what it is. Young traffic engineers grew up in a permissive age. You don't gain the respect of your children if you tell them the penalty for a curfew violation is one month of restriction, and then when they do it instead of exacting the penalty, you simply adjust the curfew to the time the child decides to come home. Instead of respect, that engenders total disregard for authority.

Not only should we go to 55 for the national good, but we should increase speeding fines to the point that the speeders "get it." And enforcement should be resolute.

Only then should we consider moving to 60 MPH as cars become more aerodynamic. Just my opinion.

Why does this have to be an all-or-nothing choice?To determine which you think is more effective.

Of course a lot of people here would favor a 55 speed limit AND strict enforcement - the question is which has more impact.

the 4 lane i used to drive to work had a speed limit of 65. i was one of the few who even got close to that, and i would have had to speed up to get there. it's the indifference to the speeding and the attitude that somehow it's an entitlement that needs changing.

setting it to 55 perhaps will slow some of them down to 65.

To determine which you think is more effective.

Of course a lot of people here would favor a 55 speed limit AND strict enforcement - the question is which has more impact.Oh, I guess if I had to pick one I'd choose strict enforcement of the current too-high limits, only because I think 55 is 5 mph too low, especially on downhills. But I don't really like either choice. Strict enforcement sure will never happen in Oregon, with the lowest patrol density in the west at less than 500 sworn officers for the whole state. 55 is even worse, and god knows I don't want us to be subjected to the likes of Convoy, Cannonball run I/II/III, Smokey and the Bandit I/II/III and Dukes of Hazzard again -- all which were a direct cultural response to the original 55mph limit.

I still think it's a false choice, and that 55 is the wrong number to be talking about. It's an arbitrary number that was pulled out of thin air (presumably because that was the limit from 1974-1985, when FWIW cars were a LOT less aero) and all these articles are suddenly showing up on this site talking about 55 -- and people here seem to be jumping on the 55 bandwagon -- without any reasonable discussion of whether that's the best number. Even I will not always keep my speed below 55. If the law goes to 55 I will continue to drive 60-ish on rural freeways, as I always did back in the days when the limit was 55. If that makes me an outlaw, so be it.

I've found the most effective way to upset people without lowering myself to flaming or trolling is setting up a poll - someone is going to be unhappy about the way it's setup nearly every time.

I can think of some other controversial poll choices on this topic (getting people to slow down and save gas):

putting speed cameras everywhere
speed bumps (primitive)
setting the speed limiters on cars to say... 70mph.
take away driver's license a lot easier

Having grown up <10 miles from Wisconsin and often had to travel across the state to visit relatives, I well remember the days when 56 mph on I-94 meant you got nailed.

Growing up in WI with a father in law enforcement conditioned me to think I will get pulled over for going 56mph in a 55!

Growing up in WI with a father in law enforcement conditioned me to think I will get pulled over for going 56mph in a 55!

What a contrast! My father was in law enforcement. too. He taught me to drive aggressively and told me that 5 mph over the posted speed limit was okay.

55 is the wrong number to be talking about. It's an arbitrary number that was pulled out of thin air (presumably because that was the limit from 1974-1985, when FWIW cars were a LOT less aero)

55 IS somewhat arbitrary, but it's worth considering that today's cars may have a lower coefficient of drag (Cd) than older vehicles but the drag is the Cd multiplied by the frontal area (and the square of the speed). The recent bloating of cars has increased their frontal area, which may offset the improvement in Cd.

Today's cars are also heavier due to this bloating. The bloating is due in part for the need for larger crush zones to deal with crashes at higher speeds, which, if we were going slower would not need to be as large. The weight of a vehicle is a primary factor in fuel consumption. So reduced speeds can save fuel in other ways.

... the drag is the Cd multiplied by the frontal area (and the square of the speed). I believe it's the cube of speed, not the square.

I believe it's the cube of speed, not the square.
According to Wikipedia
http://en.wikipedia.org/wiki/Air_resistance
the drag force varies as the square of the velocity, the power lost to drag varies as the cube of velocity.

But the point is that either way it's a steep nonlinear dependance.

I think of all the aero stuff on the Insight and then think about how I try to drive it at speeds where aero drag is much lower and all that aero stuff therefore isn't having a big effect...

It's a strange world.

I think it was in RI., but can't be sure. It was northbound. Only reason I remember is that I have never seen one with a 55 minimum before - ever!

I was just up that way earlier this week. In CT, I-95 has a minimum speed of 40 and a maximum between 50 and 65, with most of the eastern section at 65. In RI, the limit is 65, minimum 55. While in CT, I drove at about 50, with a variation of low 40s to high 50s for DWL over the rolling hills. In RI, I kept the minimum in the high 40s and nobody seemed to mind. It was sparse midday traffic and there were no protests from anyone passing by.

That tight range of 55-65 is probably because I-95 is a congested road with only two lanes in each direction, and speed differential is usually more dangerous than high speed alone.

One encouraging observation is that these midday drivers seemed to be keeping at or below the limit on the major roads. Driving at 50 and above in a 65, I found quite a few people following me at that speed, and those who passed weren't going much faster. I can only hope they were getting the same MPG boost I was seeing. The in-dash FCD was reading about 38mpg at 55-60, and it'll go over 40mpg during DWL runs in the high 40mph range.

Over that whole tank, which included three days of stop-n-crawl traffic in Boston and through the poorly timed traffic lights in Quincy/Hingham, I still nailed over 33mpg average. So I'm sold on the 55 limit, and it seems like that's becoming more popular these days!

-Chris

I'm all for that.. but I don't see it happening til after the election,doing it now would be political suicide for the GOP.

I hate 55 mph, and I get pissed off at people driving so slow! I go 65 mph in 60 to 70 mph zones because all my ride data is calibrated to that!

You need 65 or 70 mph when you do really long road trips. Don't want Chicago to Houston to be a 3 day trip instead of two!

I hate 55 mph, and I get pissed off at people driving so slow! I go 65 mph in 60 to 70 mph zones because all my ride data is calibrated to that!

You need 65 or 70 mph when you do really long road trips. Don't want Chicago to Houston to be a 3 day trip instead of two!

I still don't see how driving 55 can make an 1100 mile trip a 3 day trip. I drive from PA to Tampa, FL, 1100 miles, same as your trip. With the CC set for 55mph it took me 24 hours including rest stops. 1100miles/50mph=22hrs. Even if you took the recommended 15min break for every two hours driving, 2.75hrs, and an 8 hour sleep at the halfway point. Your grand total would only be 32.75 hours or less than 1.4 days.

65 to 70 mph is not conducive to hypermiling in any way. I am not sure what you mean by your ride data being calibrated and am really confused as to why people driving 55 in the right hand lane would, as you say, piss you off?