The Z’s standard lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane. A lane departure warning system costs extra on the 911.
The Z has a standard blind spot warning system that uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them. A system to reveal vehicles in the 911’s blind spot costs extra.
To help make backing out of a parking space safer, the Z’s standard Rear Cross Traffic Alert uses sensors in the rear to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. The 911 doesn’t offer a rear cross-path warning system.
The Z’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The 911 doesn’t offer a driver alert monitor.
Both the Z and the 911 have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, front seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights and rearview cameras.

