This was a great purchase at a great price! I installed it on my Lincoln Navigator and it gave me the sound I ever wanted! I just did an axel drop but the sound isn't quite overwhelming. At idle the noise is a pleasant hum, but when you step on the gas. Then it opens and howls with a sound that will draw everyone's attention! I absolutely love what it has done for my sat nav, it makes all the great sounds a 5.4 DHOC Ford engine can make!