Throughout the years, body shells are replacing space frames in every racing car category. 

424 Chassis Bonded Assembly

424 car chassis is made of several components listed below:

424 chassis parts

424 sub assemblies

424 Sub Assemblies

On a Le Mans car, floor, wings and body panels are also manufactured in composite materials, in addition to the chassis. Here are some of the sub assemblies you can observe on the image:

Body Shells are made of high performance Composite Materials

Composite materials have very interesting strength-to-weight ratios and have replaced other materials such as aluminium for race cars chassis construction. There is a wide variety of resin and fibres combination which enables to find the right material for each application. Here are some general characteristics that must be kept in mind when considering composite materials:

Body Shells Manufacturing

Body shells are lighter and stronger but more expensive to manufacture. Body shells require surface tooling (pattern and moulds) whereas space frames only require welding jigs. Tooling is required to build a smooth, accurate surface:

A core embedded in 2 laminate layers

Glickenhaus SCG007 bodywork in composite materials

Internal bonded beams strength test

The Chassis: a key element for dynamic behaviour

The structure of a racing car is made of components assembled in series for strength and low weight:

If one of the element is not stiff enough, the complete car dynamic behaviour will suffer.

The Chassis is a key element for Safety

Structural components are subject to very strict safety tests by the FIA. There is a lot of work required to optimise those structures, keep the weight down, while ensuring those tests are passed at the first attempt for homologation.

Dynamic crash tests are also mandatory to homologate the car. These are still difficult to simulate. We use a simple model to evaluate the behaviour of the structure and we then have 3-4 variations of the structure (different laminate thickness) that we test during the FIA homologation.

Rollover structure test