What is the definition of a "car length"

Discussion in 'Fred's House of Pancakes' started by Codyroo, Sep 1, 2010.

  1. Codyroo

    Codyroo Senior Member

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    I tried doing a google search and came up empty. What is the distance of "a car length"? 15 feet? 20 feet? 25 feet? 30 feet?

    When driving behind someone (say on the freeway), I tend to stay 2 seconds (or more) behind them. Say at 60 mph (88 feet/second) this is 176 feet. Some would say keep 6 car lengths behind someone when driving 60 mph. But how long is that?

    Weigh in!
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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  3. hyo silver

    hyo silver Awaaaaay

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    The two second rule is much easier to follow, even if you knew how much a car length was. It works at any speed, except in urban traffic where it's almost safer to tailgate than be cut off.
     
  4. Codyroo

    Codyroo Senior Member

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    Here's an interesting tidbit I found

    http://www.dmv.ca.gov/pubs/curriculum/Unit 7.pdf

    Page 6 - rules of the road - tailgating - they want you to stay back 3 seconds. Good God! That means I'm tailgating for a decent proportion of my driving day. Ugh.
     
  5. bisco

    bisco cookie crumbler

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    i'm in for 20':D
     
  6. xs650

    xs650 Senior Member

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    Very few private passenger cars were ever 20 feet long. The average back in the olden daze when the 1 car length per 10mph rule was drivers ed wisdom was about 15 feet. That is essentially 1 second which isn't enough unless you are really on top of your game. 2 seconds is the closest you should follow if traffic allows it. If you are following at 2 seconds and people keep cutting in front of you, then you might consider one second.

    3 seconds is better but not realistic except on the open road.
     
  7. Boo

    Boo Boola Boola Member

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    @xs650

    +1

    That was what I had figured out too ... the old 1 car length per 10 mph rule is roughly the equivalent of the 1 second rule.