In addition to adding two small resonators to tame the higher-pitched rasp when getting on the gas hard, I will be adding 1/4-wave "j-pipe" resonant tubes to eliminate the drone from 1600-1800 RPMs. They will need to be about 30" long per side. Luckily, there is plenty of room back there to add these.

Total cost, including the resonators to be added is just under $300.

__________________
2007 E70 4.8i