To maximize occupant safety, the front seat shoulder belts of the BMW 8 Series have pretensioners to eliminate dangerous slack in the event of a collision and force limiters to limit the pressure the belts will exert on the passengers. The Toyota Supra doesn’t offer pretensioners.
The 8 Series’ pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The Supra doesn’t offer pre-crash pretensioners.
The 8 Series has a standard PostCrash iBrake, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The Supra 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 8 Series offers all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The Supra doesn’t offer all-wheel drive.
The 8 Series offers an optional Surround View Camera to allow the driver to see objects all around the vehicle on a screen. The Supra 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 8 Series and the Supra 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, driver alert monitors, available blind spot warning systems and rear cross-path warning.
The BMW 8 Series weighs 502 to 1510 pounds more than the Toyota Supra. The NHTSA advises that heavier cars are much safer in collisions than their significantly lighter counterparts.

