Opel Astra TCR Racer Aero Package
In order to be successful in the Touring
Car Racer Series, a vehicle has to have excellent aerodynamics and undergo
meticulous wind tunnel testing.
Aerodynamic efficiency is the result of
a well-balanced ratio of downforce and drag, which is something engineers need
to keep in mind when building a car that's meant to tackle high speed corners
as easily as it blasts through main straights.
Opel claims that the reigning "Car
of the Year 2016" already has an outstanding drag coefficient of 0.272,
which makes it well-suited to serve as the base for a track-oriented car.
Compared to the production model, the
TCR has gained 1,950 mm in width, the maximum permitted by the
regulations. While the bumpers, fenders and side panels have been modified,
it's the front splitter and the rear wing that help create most of the
downforce.
The rear wing needs to be carefully
positioned so that it won't protrude from the roofline. In order to figure out
a compromise between drag and downforce, Opel engineers built the front
splitter as flat as possible, though steep enough to keep the front axle stable
under braking and prevent understeer.
As for gathering sufficient data, the
team went to Stuttgart University and used their wind tunnel. "It has a
rolling floor and can simulate speeds of up to 250 km/h. That makes it ideal
for our purposes", explained Opel Motorsport exec Dietmar Metrich.