BMW Heaven - The Knowledge Base 2.0

  • Increase font size
  • Default font size
  • Decrease font size

Z4 - E89 (2008 - ...) - Body and Safety

User Rating: / 247
Article Index
Z4 - E89 (2008 - ...)
Design and Technology
Design: Modern, Emotional, Authentic
The Retractable Hardtop
Drivetrain: Straight-Six in the Roadster
Body and Safety
Equipment: Driving Pleasure All the Way
Flexible Production
All Pages

Body and Safety: Maximum Stability for Unrestricted Driving Pleasure.
- Optimised space comfort and greater variability.
- Extremely stiff passenger cell and high load-resistant body structure.
- Highly efficient restraint systems for maximum occupant safety.

The new BMW Z4 Roadster combines thrilling design with comfortable and sporting driving characteristics. At the same time this outstanding two-seater excels through the significant increase in space it offers both the driver and passenger as well as a supreme standard of occupant safety. Indeed, the extra-strong body of the new Roadster contributes to both driving safety and dynamic performance on the road, the intelligent combination of innovative and proven materials plus the most advanced production technologies giving the new BMW Z4 excellent stability. Highly effective, centrally controlled restraint systems, finally, guarantee first-class protection in all kinds of collisions.
The new BMW Z4 is larger than its predecessor: The new Roadster is 4,239 millimetres or 166.9" long, 1,790 millimetres/70.5" wide, and 1,291 millimetres/50.8" high. Wheelbase, in turn, is 2,496 millimetres or 98.3". These larger dimensions mean both extra spaciousness and larger storage capacities all in one.

Optimised visibility, more space.
With its retractable hardtop, the new BMW Z4 comes with ­extra-large windows for optimum visibility. Compared with its predecessor, all-round visibility is up by approximately 14 per cent and the side windows are no less than 40 per cent larger. Visibility through the rear window, finally, is even up by 52 per cent.
Access to the passenger compartment is likewise more convenient than before, door openings 26 millimetres or 1.02" larger than on the former model facilitating access to the driver’s and front passenger’s seats also with the roof closed.
Headroom is up by 5 millimetres or almost 0.2" over the former model and extra width inside the passenger compartment again provides a better feeling of space: With the overall width of the car up by 9 millimetres or 0.35", shoulder room is 20 millimetres/0.79" and elbow room 43 millimetres/1.69" greater than before.


Generous seating and variable storage of luggage.
The versatile luggage storage concept plays a significant role in making the new BMW Z4 particularly suitable for both everyday use and long distances.
The configuration of the luggage compartment alone offers a wide range of individual use and function, with luggage capacity in the Roadster ranging from 180 litres/6.3 cubic feet with the roof down all the way to 310 litres/10.9 cubic feet with the roof closed, giving the new BMW Z4 greater luggage capacity than any other model in its segment.
A further important point is that maximum load is up by 30 kg or 66 lb over the former model to 330 kg or 728 lb.
The practical value of the car is further enhanced by a wide range of standard and optional features including items such as the variable luggage compartment cover, a side storage box again with a cover on top, and optional through-loading including a transport bag able to accommodate up to two pairs of skis measuring up to 170 centimetres/66.9" in length. And once the loading process has been completed, the hardtop opens without the slightest problem even when carrying such bulky luggage.

Aerodynamic qualities for enhanced dynamics and driving comfort.
Dynamic performance and superior efficiency, as well as the driving comfort of the car, all benefit from the excellent aerodynamic qualities of the new BMW Z4.
The optimised design of the front air dam, the side-sills and the rear end serves to significantly reduce air resistance, just as air draught within the interior has been optimised by specific improvements such as the side windows extending far to the rear in order to reduce air swirl.
The wind deflector designed specifically for the new BMW Z4 develops its superior effect for the car’s occupants also at high speeds, ensuring supreme motoring comfort even at speeds above 200 km/h or 125 mph.

Comprehensive safety concept tailored to the BMW Roadster.
The unique standard of the new BMW Z4 is borne out also by an exemplary range of safety features based on the high safety standard already applied to BMW saloons and meeting the most demanding requirements in today’s world.
Among other features, high load-resistant carriers, the optimum use of deformation zones, the extremely stiff passenger cell and highly efficient restraint systems ensure exemplary safety in an accident. Accordingly, the new BMW Z4 boasts all the features to achieve optimum results in all relevant safety and occupant protection tests.

Maximum safety on minimum weight.
The development engineers at BMW have achieved particularly impressive results in designing the structure of the body which, despite the absence of a hard roof normally taking up significant loads, offers excellent stiffness and body strength. Impact forces acting on the new BMW Z4 Roadster, for example, are absorbed dynamically by additional deformation zones giving in at exactly defined points and converting impact energy into a controlled deformation process.
Precisely to ensure this high standard, BMW’s development engineers have given the car a perfectly balanced network of support elements on the floor pan, in the side frame, on the bulkhead, in the roof and on the luggage compartment partition to absorb impact forces entering from outside. The new BMW Z4 thus features high-strength panels in large bearer structures with appropriate reinforcements strengthening the body to the greatest possible extent. Impact forces are diverted in an optimised process through the appropriate distribution of forces on several body components, the distribution of loads serving in severe collisions – above all with loads acting on one side of the car – to guide the incoming energy to the opposite side and protect the bulkhead area in the footwells by means of appropriate dynamic deformation zones.
The specially designed floor structure, incorporating the engine mounts, drive shaft reinforcements and the single-cell doorsill concept reinforced by additional plates, likewise ensures optimum transmission of impact forces.
Around the doors, side impact supports, reinforced doorsills, the seats themselves and the instrument panel support between the A-pillars ensure more than adequate stability on the side structure.
The rear deformation zone is made up of two longitudinal load-bearing bars, the floor of the luggage compartment, the rear panel and various other reinforcements. In a rollover the passenger cell with its extremely strong A-pillars and rollbars behind the headrests maintains the occupants’ survival area.


Frontal airbags and head/thorax airbags integrated in the seats.
Within the interior, carefully balanced and centrally masterminded restraint systems ensure appropriate occupant safety: The frontal and head/thorax airbags, belt latch tensioners and belt force limiters are activated by sensor-controlled safety electronics as a function of the type and severity of a collision. The head/thorax airbags are integrated in the outside of the backrests and inflate in the event of a side-on collision over an extra-large area extending from the lower edge of the backrest all the way to the upper edge of the headrest, thus offering the driver and passenger optimum safety at upper body and head level, regardless of their personal seating position and regardless of whether the roof is open or closed.
A further point is that optimised connection of the seat belts ensured by the belt latch tensioners featured as standard and thus avoiding any slackness of the belts on hip and chest level guarantees even better restraint reducing the risk of injury to a minimum.

Bi-xenon headlights featured as standard, adaptive headlights as an option.
BMW’s excellent lights technology is a further outstanding feature in the safety concept of the new BMW Z4. The lights system comes as standard with bi-xenon headlights and as an option with adaptive curve lights ­automatically moving in the direction of the steering wheel.


Daytime driving lights already required by law in some countries are featured in the corona rings integrated in the headlight housing. A deceleration-related brake light system, in turn, enhances active safety to an even higher standard, the lights technology combining proven lighting systems with the latest and most innovative features. This comes out most clearly on the striking rear lights integrating several light functions such as the brake lights, foglamps and reversing lights as well as the direction indicators.

Last Updated on Monday, 12 April 2010 14:38  

Latest specifications

2008 Alpina D3 Biturbo LCI Sedan (E90)

2008 Alpina D3 Biturbo  LCI Sedan (E90)
View full specifications

2010 BMW 135i (E82)

2010 BMW 135i    (E82)
View full specifications

2011 BMW 640d A Coupe (F13)

2011 BMW 640d A  Coupe (F13)
View full specifications

2010 BMW 1 Series M Coupe (E88)

2010 BMW 1 Series M   Coupe (E88)
View full specifications

1994 BMW 740i A Sedan (E38)

1994 BMW 740i A  Sedan (E38)
View full specifications

Latest pictures