[Vwdiesel] Driving

[Arkady Mirvis]

Bravo, Erik!
During decades of years of driving in USA I've seen a lot of what you just 
described and much, much worst.
I recall what happened years ago on interstate Rt. 80 in NJ. Cutting off by 
a jirk resulted in a  rig with 6000 gallons of gasoline to brake, then being 
hit from behind by another container rig. Gas tank split open and a huge 
fire erupted right on concrete overpass. Miraculously the driver of the gas 
truck run away and survived. The container rig driver burned alive. The fire 
was immense. Gasoline river run down under the bridge and the bridge 
collapsed. You can imagine how it affected the traffic on a road connecting 
California and New York, where thousands of trucks stream thru.
I didn't see so far anything like that in Portugal yet, but what I see daily 
is very close. Portuguese drivers are the worst in Europe (by statistics), 
but the big part of them are masters of driving. The latter feel their 
machines to the utmost. Only few roads are good, streets in cities and 
towns, built in Mid Ages, are narrow, waivy and yet one can often see a full 
size city bus navigating there, inches from hitting the houses with their 
side mirrors at
30-40 km speed.  The bigest danger here are tri -and quadrocycles, antiques 
motorcycles and bicycles. They are often with no lights, drivers in dark 
clothes. This nation of 10 millions has over 2 millions of cars, trucks not 
included, driving is in mostly very difficult conditions. On good roads 
everybody passes me slow driver. They drive faster than 100 miles per hour. 
I am positive that per capita Portugal has more MB and BMW than any country 
in the world.  Police is hardly present on the roads, I haven't seen any 
ambush in 2.5 years. I rarely see GNR (Guarda Nacional Republicana - road 
police), they occasionally (2-5 officers) stop vehicles to check the 
documents. They are very polite and punish if papers aren't in order. The 
fines are very steap ( up to $500) and must be paid on a spot. One is lucky 
if he has a credit card.
In 2.5 years I've seen only 2 Westies.
Ark Mirvis
----- Original Message ----- 
From: "Erik Lane" <eriklane at gmail.com>
To: <decker at toledotel.com>
Cc: <vwdiesel at vwfans.com>
Sent: Sunday, November 29, 2009 7:29 AM
Subject: Re: [Vwdiesel] mileage


On Sat, Nov 28, 2009 at 7:47 PM,  <decker at toledotel.com> wrote:
> Hi Eric;
> You and Val can argue about physics but in a real world of stopping a
> big diesel tractor and a long semi-trailer or a set of doubles I can tell
> you about how they brake since I have done it for 50 years. If you are 
> empty
> and in a panic stop you put on the air and the tires will almost 
> invariably
> smoke (skid) and then bounce so you have to back off on the air till they
> start rolling again and have some adhesion to the pavement. Between air 
> time
> and skid time you do very little braking. If you are loaded to say 100,000
> pounds you have so much mass moving that when you put on the air and the
> wheels lock the tires skid and you aren't stopping well. If you are 
> lightly
> loaded you have a pretty good balance between the mass you are trying to
> stop and the adhesion your tires have on the pavement so you stop rather
> quickly. Read about ABS brakes. A big share of you new cars have them
> because the computer can sense when the tires would skid and can modulate
> brake pressure to prevent you from skidding them no matter how had you 
> press
> on the brake pedal.
> One of the tough things about driving a big rig in traffic is when you
> leave enough following distance to be safe most likely some stupid car
> driver will pull in front of you and behind the rigs in front of him.
> Apparently they don't comprehend that they have just driven their mobile
> coffin into emanate danger till you can back off enough to have a safe
> following distance. Sometimes it feels like you are driving your truck
> backwards. When you are drafting you don't bother me since what is behind 
> me
> has to look out for themselves. Last year we had a driver with a set of
> doubles just barely get stopped because some fool in a motor home just
> stopped in the road in front of him for no apparent reason. It would not
> have been a problem except that the new Ford pickup that was following to
> close got eaten up when he hit the back trailer. It probably was 
> inattention
> since he should have been able to stop faster than our doubles driver. He
> wasn't hurt it totaled his pickup.
> Brian Decker

If the tires start bouncing then of course that would change things.
Is it the heat that does that? I'd like to see some actual tests that
scientifically show that there is a significant difference with the
different loadings.

With that said, I drive much more carefully when pulling large
trailers and loads. They feel different. But I still suspect that with
operating brakes and all wheels locked up they'd stop pretty well.
Maybe the large tires are made for economy and have much less grip on
the road than consumer tires, but other than the material differences
the stopping distance should still be about the same. Unless there's
more advanced things that I don't know about. In that case I'd *love*
to be educated.

Erik
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