Acura ILX 2021 Owner's Manual page 475

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:
50 mph (80 km/h) 65 mph (104 km/h)
84 feet
26 meters
1.1 sec
111 feet
34 meters
1.5 sec
155 feet
48 meters
2.1 sec
215 feet
66 meters
3.0 sec
uuAcuraWatch
102 feet
31 meters
1.1 sec
139 feet
43 meters
1.5 sec
202 feet
62 meters
2.1 sec
285 feet
87 meters
3.0 sec
Continued
TM uAdaptive Cruise Control (ACC)
473