Originally Posted by RPiM5
I always believed that it was a 1.5hp gain on the E60 M5 with the charcoals removed, but this included a slightly better engine response. Who knows!
I believed it to be quite small, more of a throttle response and breathability enhancement. However, I did read way back in '09 somewhere on the thread about the E60 deletion there were folks citing dyno results of upwards of 20HP. Again, I'm not suggesting this at all...rather, if it buys the former - great! Also, I am interested in seeing if any cars outside of North America have the filters. That would be telling.