Getting Down

Supercars will reduce downforce on the Ford Mustang and Holden ZB Commodore for 2020 in the latest bid to improve the racing and achieve better parity between the cars.

- Andrew Clarke

Supercars has bowed to pressure and announced it is reducing downforce on its racing cars from 2020.

The Ford Mustang and Holden ZB Commodore will be re-tested through an improved process over the offseason, with downforce reduced by around 15 percent.

The hope is that a reduction in downforce will improve a car’s ability to follow and then increase overtaking opportunities. It’s seen as a long-awaited redress.

Over time the amount of downforce has slowly crept up, adding up to what is measured as 350kg of downforce at 200km/h, as new models were introduced since the implementation of the Car of the Future regulations from 2013. Each manufacturer and. design team was looking for an advantage and playing the system. Ride heights, pitch angles and the like all used to fit the figures and the test but not to create parity.

One of the most significant cars in terms of aerodynamics in Supercars was the Volvo Polestar S60. Scott Burch from Garry Rogers Motorsport was involved in that development and agrees there was incremental creep not just from that car but from all cars.

“I suppose the cars have generally gotten more aero dependent as time’s gone on,” he says.

“Because we have a very large planar surface [the front undertray], which is very close to the ground on these, which sits the leading edge a meter in front of the centre of the front wheel, and then you’ve got this huge area at the back.

“When you dip down on the brakes, you generate an awful lot of downforce on there. Anyone who steps in and gets out talks about how amazing these things are on the brakes.