TR CHEESE GRATERS

Pininfarina's design of the Testarossa body was a departure from the curvaceous boxer and even caused a bit of controversy at the time. It's side strakes or "cheese graters" that spanned from the doors to the rear fenders were actually necessary due to restrictions in some countries outlawing large openings on cars. The Testarossa had twin radiators lodged in the engine bay in the back of the car instead of having a single radiator at the front which meant Pininfarina needed to figure out a way to guide air around the car and into the radiators. 

Leonardo Fioravanti's design of the large side strakes were not only testament of Ferrari's unique style but were also very efficient as drawing in clean air to cool the side radiators on its way out ventilation slits in the rear of the car solving their potential cooling issue. At the time this was an extremely unique design feature that even aided in creating downforce which is why it lacks a rear spoiler like Lamborghini's Countach. Side strakes on supercars are becoming ever more common due to the many advantages of they provide to performance by harnessing the energy of passing air. Engineers now understand they can utilize this energy to create more downforce, increasing cooling or even decrease a car's drag coefficient.