For enhanced safety, the front and rear seat shoulder belts of the Audi S4 have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision and force limiters to limit the pressure the belts will exert on the passengers. The Alfa Romeo Giulia Quadrifoglio doesn’t offer pretensioners for its rear seat belts.
The S4’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The Giulia Quadrifoglio doesn’t offer pre-crash pretensioners.
For enhanced safety, the front seat shoulder belts of the Audi S4 are height-adjustable to accommodate a wide variety of driver and passenger heights. A better fit can prevent injuries and the increased comfort also encourages passengers to buckle up. The Alfa Romeo Giulia Quadrifoglio doesn’t offer height-adjustable seat belts.
Both the S4 and Giulia Quadrifoglio have child safety locks to prevent children from opening the rear doors. The S4 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The Giulia Quadrifoglio’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.
The S4’s standard pretensioning seatbelts also sense rear collisions and remove slack from the seatbelts to help protect the occupants from whiplash and other injuries. The Giulia Quadrifoglio doesn’t offer a whiplash protection system.
The S4 has a standard Secondary Collision Brake Assist, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The Giulia Quadrifoglio doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.
The S4 has all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The Giulia Quadrifoglio doesn’t offer all-wheel drive.
The S4 Premium Plus/Prestige has a standard Top View Cameras to allow the driver to see objects all around the vehicle on a screen. The Giulia Quadrifoglio only offers a rear monitor and front and rear parking sensors that beep or flash a light. That doesn’t help with obstacles to the sides.
Both the S4 and Giulia Quadrifoglio offer rear cross-traffic warning, but the S4 with Rear Cross-Traffic Assist also has Automatic Brake Activation (automatically applies the brakes) to better prevent a collision when backing near traffic. The Giulia Quadrifoglio’s Rear Cross-Path Detection doesn’t automatically brake.
Both the S4 and the Giulia Quadrifoglio have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, rearview cameras and available blind spot warning systems.