My brother's thoughts on ecomodding/hypermiling

[Arminius]

Last month I drafted a semi from Milwaukee to St. Paul. I stayed 3 seconds behind and my van's FE went from 18 mpg to 27.6 mpg at 60 mph.

However, the semi driver eventually called the police on me because he didn't like me behind him. No ticket - just a close call.

[superchow]

We'll be driving to Wyoming on Wednesday, and I'll be drafting whenever possible at a "safe" distance of around 3-4 cars. I like the approach of closing in until the wind noise changes (nwbabybronco).

I am expecting a 4 mpg increase in FE (up from ~38 highway to 42-ish). I'll post my results when I return to Olympia.

[Lazarus]

Originally Posted by jamesqf

Let's see: You can drive a Chevy Astrovan at 63 mph instead of 73, and go from 18 mpg to 26. Or you can drive a Honda Insight instead of the Chevy, and go from 26 mpg to 70.

Now tell me, which of these has more effect on fuel consumption? So why are people still talking about 55 mph speed limits (Which were tried before, remember?), and not building vehicles with decent fuel economy?

PS: And notice that the improvement was going from 73 to 63, but not going slower. So why 55 as the limit, instead of 65?

Not everyone can afford a insight. Lots of folks but 5-10 year old cars so it will be awhile before the trickle down hits. We need to reduce oil consumption now not 10 years from now.

He would of got more MPG at 55 then 65. Yes it has been done and it accomplished exactly what it was suppose to and also decreased the fatality rate. So we can wait another 5-10 years for the car makers to make FE friendly affordable cars or we could just bite the bullet and do something now.

[IndyIan]

Originally Posted by Arminius

Last month I drafted a semi from Milwaukee to St. Paul. I stayed 3 seconds behind and my van's FE went from 18 mpg to 27.6 mpg at 60 mph.

However, the semi driver eventually called the police on me because he didn't like me behind him. No ticket - just a close call.

3 seconds is quite a distance at 60 mph, about 250 feet, I think you must've been a bit closer
It's funny though what you can get away with depending on the situation, in heavy traffic doing 60mph you could follow at 1 second and the trucker wouldn't think twice, it lighter traffic the trucker notices what you are doing and then may have a problem with it.
I can see their side of it, I'm sure they see more stupidity than most of us. To them, a drafter is a potential rear ender and then they have to stop for all the accident report stuff. I assume they don't get paid to stand around and wait for a new trailer either.
Ian

[johnpr]

Originally Posted by jamesqf

PS: And notice that the improvement was going from 73 to 63, but not going slower. So why 55 as the limit, instead of 65?

the reason for 55 speed limit is because when the speed limit is 65 people drive 75, when the speed limit is 55 people drive 60-65 and that is like that all over the country, some places are worse, when i lived in ft lauderdale speed limit on the highway was 65 and there where many people who drove 90+ (90 was my speed and there was still people passing me!!)

[Gregte]

Originally Posted by johnpr

the reason for 55 speed limit is because when the speed limit is 65 people drive 75, when the speed limit is 55 people drive 60-65 and that is like that all over the country, some places are worse,

This seems terribly unfair to the conscientious law abiding sole. He has to drive 55 if the posted speed limit is 55.

[nwbabybronco]

^ Just consider the speed limit sign to have a typo, then.

As far as switching cars, we're talking about a huge cultural change. Granted that may be coming, but I can't see it that fast. Where are the old cars going to go? Just roll the problem down hill to the next poorer person? Send them to Bhutan? The process of recycling all our Excursions into EV1s will not come easy. In the meantime, while working toward that, we can make the best of what we have.

Besides, what's the Honda line? "Respect the van. Many of today's families started in one."

Also, while I don't have any figures to support a conclusion, it seems to me the embodied energy in producing a new FE car would take a while to be recovered in fuel savings. I can't say how long, though, with 50mpg difference.

[ankit]

So is drafting beneficial also at lower speeds around 45-50 MPH? I can also definitely feel the difference when I get into or out of a draft, but I am never as close as 20'. Maybe something like 50' is as close as I will go. Those are amazing numbers for a Van of that size, but does it run on diesel?

[ebacherville]

an astro van is a mid sized van, there all gassers.. there smaller than the full size vans and there pretty decent aerodynamics vs a full size van..

i got pretty decent milage in my full sized fuel inject ford van.. got a respectable 20mpg in it. pretty good for a full size van with a small v8.

[jamesqf]

Originally Posted by Lazarus

Not everyone can afford a insight. Lots of folks but 5-10 year old cars so it will be awhile before the trickle down hits. We need to reduce oil consumption now not 10 years from now.

Funny how not everyone can afford an Insight ($20K new), or for that matter a 10-20 year old Civic or CRX that will get ~40 mpg, but they could afford $30K or more for that jacked-up pickup or SUV they're driving now :-) There are cars out there that get decent mpg, and they've trickled down all the way to the bottom of the used car market.

As for the 55 mph speed limit, why? Not only has it been tried, and rejected, there are lots of places/situations where it's counterproductive. For example, in hilly terrain I can get better mpg at 75 than 55, simply because I have to downshift a couple of gears to climb at 55 (which shifts the VTEC, and cancels lean burn). On downhills I can go 75 mph using zero gas, which conserves momentum for the next uphill. (It really irritates me when the cars in front brake on downhills.) Maybe 55 works in the flatlands, but in my experience with the Insight, I often get worse mpg at 55 than either 45-50 or 60-65.

Now if you really want a legislative change that will affect gasoline consumption, simply require that all cars have real-time fuel consumption displays. Let people see their real fuel economy, instead of shoving dogma down their throats.