BMW 7 Series: New Chassis Systems For F01/02

Through intelligent design layout and optimum package space utilization on the new F01/F02, the basis has been created for distinctly increasing the driving dynamics while improving comfort and vehicle handling.

At virtually identical wheel loads, a greater track width and a larger wheelbase have been realized compared to the predecessor, the E65.

The development of the new generation chassis and suspension systems in the new F01/F02 focused on revolution instead of evolution. The aim was to set a new bench-mark.

The lightweight construction philosophy was consistently pursued in the design of the chassis and suspension systems. This is reflected in the widespread use of aluminum, representing an important contribution to increasing comfort and reducing CO2 emissions.

For the first time, a BMW Sedan is fitted with a double wishbone front axle made of aluminum, a steerable integral-V rear axle, BMW integral active steering (IAL) and the innovative damper system, the 2nd generation vertical dynamics control (VDC 2).

The integrated chassis management (ICM) intelligently links all chassis and suspension control systems, thus achieving a new level of functional quality. Further highlights include "Dynamic Drive" (ARS) and a fully variable power steering pump to improve fuel economy.

CHASSIS SYSTEM COMPONENTS DIMENSION DESCRIPTION CHART

Chassis and Suspension Comparison

CHASSIS AND SUSPENSION COMPARISON CHART

Track Width

The size of the track width at the front and rear has a decisive influence on the cornering characteristics of the vehicle and its tendency to roll.

• The track width should be as large as possible, however, it cannot exceed a defined value in relationship to the width of the vehicle.
• The fully deflected (spring compressed) wheel turned at full lock on the front axle must not scrape or snag in the wheel arch cutout.
• A certain degree of clearance for fitting snow chains is required on the drive axle (irrespective of whether this is the front, rear or both axles).
• The wheels must not make contact with any chassis or body parts when the suspension springs fully compress and rebound.

Wheelbase

The wheelbase -measured from the center of the front axle to the center of the rear axle has a decisive influence on the vehicle handling properties.

A large wheelbase compared to the length of the vehicle permits favorable accommodation of the vehicle occupants between the axles and reduces the influence of the vehicle load on the overall load distribution. Short body overhang at the front and rear reduces the pitching tendency.

A short wheelbase, on the other hand, provides favorable cornering characteristics, i. e. a smaller turning circle at the same steering lock angle.

The outstandingly balanced values on the E65 result in safe, superior and agile vehicle handling characteristics that represent the standard in the luxury class segment also for the future. These technical data are the prerequisite for achieving the top position in its class. In terms of driving dynamics, the F01/F02 will assume a leading position without forfeiting driving and rolling comfort compared to the competition (with comparable equipment).

READ NEXT: