Clk 550 upgrades?
I believe Kleeman released a supercharger which should result in about 480hp.
You can contact PowerChip, Speed Tuning USA, RennTech, Kleeman, or Brabus and see what kind of ECU upgrades they have (should range from $300-$1,000 and give you about 15hp).
I'm sure that the above listed tuners are working on headers and forced induction for these cars.
Good luck and keep us updated.



