does driving close to car in front on mway save fuel?

cyclonebri1

darich wrote: »

ahem......try "many"

Ohhh fook don eet ageen,

mickamike404

In replying to this STUPID question,some of you
must be !!!!!!.

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Gene_Hunt_2

mickamike404 wrote: »

In replying to this STUPID question,some of you
must be !!!!!!.

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Like you did?

spike7451

The car in front was probably braking all the time to try & get rid of the bum hole who was tailgating him!

mickamike404

Gene_Hunt wrote: »

Like you did?

Yes Gene but with some of the reply's it needed saying.
bit sad, but there you go.

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darich

ScreamingSoul wrote: »

Aside from the OP being a WUM, it's not as stupid a question as you may think.

Mythbusters did a fuel economy experiment. Following a HGV travelling at 55mph gave the following results:

With a baseline of 32MPG

Distance from HGV MPG Difference
100’ 35.5 11%
50’ 38.5 20%
20’ 40.5 27%
10’ 44.5 39%
2’ 41 28%


I wouldn't advocate travelling at 55 mph, 10 feet behind a HGV to save a bit of fuel but with the quality of braking systems on cars and the time taken for a HGV to come to a stop, surely travelling 100 feet behind can't be that bad.

I think everyone agrees that in principle it would work.....F1 cars do it to reduce the air resistance and get an extra couple of MPH and pass the car they've been tailing.
Same thing with a car behind a truck.

The thing is the truck may take longer to stop and it may be quicker stopping a car now than it was 30years ago......but one thing hasn't changed that much......the driver.

An alert driver will travel approx 1foot per mph in the time it takes to go from accelerator to brake. So that allows 45feet of thinking time....assuming you're serious about travelling 100 feet fehind a 40tonner.
Even if you can see the truck brake, decide that you need maximum brakes and then start the movement of lifting the accelerator, you've travelled around 75feet.

So travelling behind a lorry at 55mph in perfect conditions and totally alert you'd need an absolute minimum of 75ft to think and then around 130feet to stop the car....205ft.
And that's before you deal with the child in the back seat, change radio station, glance at speedo, check mirror all of which will distract you from the truck you're too close too and increase your thinking distance considerably.

And it doesn't need to be the HGV coming to a stop that's the problem - its load could fall off, blow a tyre, hit a stationary object and stop dead or drive over something that a car is too small to and you collide with it.

100ft is around 50% of the distance you need at 55mph.

Gene_Hunt_2

mickamike404 wrote: »

Yes Gene but with some of the reply's it needed saying.
bit sad, but there you go.

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Yet you keep posting.;)

Glitzkiss

Did I miss the "which forum is more argumentative/gullible poll" run joint on DT and motoring.

I suspect Tod has met his spiritual match here. He can troll for days and some people won't notice :whistle:

cyclonebri1

ScreamingSoul wrote: »

Aside from the OP being a WUM, it's not as stupid a question as you may think.

Mythbusters did a fuel economy experiment. Following a HGV travelling at 55mph gave the following results:

With a baseline of 32MPG

Distance from HGV MPG Difference
100’ 35.5 11%
50’ 38.5 20%
20’ 40.5 27%
10’ 44.5 39%
2’ 41 28%


I wouldn't advocate travelling at 55 mph, 10 feet behind a HGV to save a bit of fuel but with the quality of braking systems on cars and the time taken for a HGV to come to a stop, surely travelling 100 feet behind can't be that bad.[/QUOTE]


By any calculation, it is a stupid question.

Untill the days of comp controlled traffic the human element precudes it from working.


How long does it take a hgv that hits a staionary one in front or one gone over the barrier to stop??? get my drift?