In the sound-proof and bullet-proof test cell at Hirsch Performance, the Saab engines are taken to their extremes. The worst possible ambient conditions are simulated by regulating temperature and pressure of intake air to simulate desert heat or high altitude alpine passes. Computer-controlled water and charge air cooling systems are used to simulate poor cooling as enocuntered for example in traffic jams at high temperatures. During these extreme tests, the engines are closely monitored to ensure that no critical components such as cylinder head, catalyst or turbocharger become overheated, overstressed, or overspeeded, while keeping a close eye on emission levels so that they are not exceeded.