Honda Civic 2017 Owner's Manual page 500

The higher your vehicle's following-speed is, the longer the short, middle, long or
extra long following-interval becomes. See the following examples for your
reference.
Following-interval
Short
Middle
Long
Extra Long
When the Set Speed is:
80 km/h 104 km/h
25.4 metres 30.6 metres
1.1 sec
33.4 metres 41.9 metres
1.5 sec
46.9 metres 60.9 metres
2.1 sec
65.1 metres 86.2 metres
2.9 sec
uuHonda Sensing
1To Set or Change Following-interval
The driver must in all circumstances preserve a
sufficient braking interval from the vehicle which
precedes it and be aware that minimum intervals or
times of spacing can be provided by the provisions of
the Motorway Code locally applicable and that it is
the driver's responsibility to respect those laws.
1.1 sec
1.5 sec
2.1 sec
2.9 sec
Continued
* uAdaptive Cruise Control (ACC)
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