Re: Effect of ABS on stopping distances (was Re: ABS ACTIVATING @ 3MPH)

[tobias.jansson@ein.ericsson.se]

I found this on the net a while ago:
 http://www.veta.se/msc101.htm
They use an Audi 100 Avant Quattro to do tests with ABS, Quattro and
driving safety. 
Unfortenately for you guys, most of the text is in swedish, but if you
click on "låsningsfria ABS-bromsar" in the beginning of the page,
and then click on the "här tips om hur du ska bromsa med ABS" link,
you will find a page about ABS-braking and safety in english :)

Regards,
Tobias Jansson (200TQ -90)


On  3 Dec, Chris Newbold wrote:
» There was an article in Road & Track, I believe it was July 1997,
» in which they tested the effects of ABS on stopping distances under
» various conditions.
» 
» The car used in the test was a 600-series Mercedes, which they rigged
» to allow the ABS to be turned off; they used the stock tires (Michelin
» mumble, mumble Energy).
» 
» They tested on a number of surfaces using four different methods: 
» 
» 	1) ABS on, stomp the pedal and hold it until stopped
» 	2) ABS on, full breaking but driver modulation
» 	3) ABS off, stomp the pedal and lock 'em up until stopped
» 	4) ABS off, full braking but with driver modulation
» 	   (wheels locked, though?!?!)
» 
» On all surfaces, entry speed was 30 MPH, except dry pavement where the
» speed was 60 MPH; distances are in feet.
» 
» I make *NO* claim that I have remembers these numbers correctly. I
» am fairly certain, however, that I have approximated the difference
» between ABS and no ABS...
» 
» 	Method ->	1	2	3	4
» 
» 	Surface
» 	-----------	
» 	ice		220	220	150	170
» 	packed snow	170	180	195	195
» 	loose snow	180	190	150	150
» 	fresh snow	180	190	150	150
» 	gravel		90	70	52	52
» 	sand		49	50	50	50
» 	wet		35	50	90	70
» 	dry		120	140	200+	200+
» 
» The testers also mentioned that they didn't really believe in the
» "wedge" effect on loose surfaces. While "wedges" of the surface
» material did build up, they were not convinced that (smallish)
» wedges of snow, etc. could have any significant retarding effect on a
» 2-ton Benz.
» 
» As always, YMMV.
» 
» -Chris
» 1993 90CS

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