Saab will celebrate 30 years of turbocharged engines at next month's Frankfurt motor show with a limited edition model called the Turbo X. The brand is being tight-lipped on exactly what the model will be based on, but the likeliest option would be a more fiercely blown version of the recently facelifted 9-3 V6 Aero saloon, with more power than the standard car’s 247bhp, and the firm’s new asymmetrical cross-wheel drive system.Saab has also said that the car will inherit the understated cool of its 99 and 900 Black Turbo model forebears. Expect the Turbo X to feature stealthy black paint and a subtle bodykit on the outside, along with some technical enhancements that the manufacturer claims "will deliver standard-setting levels of performance for the brand". Been waiting for a 300bhp, all-wheel drive Saab? Then watch this space. We will find out more when the car is launched at Frankfurt in September.