Tuners playing with cars is nothing new, but how do you convince an owner to bring its toy to you in this era when the competition is getting more and more fierce? One answer comes from German tuner Hartge, which has recently released a video that goes further than just offering us the on-paper data.
The clip shows how the Hartge-tuned 525d xDrive performs in the real world, with the vehicle being tested on the Autobahn, with the vehicle now completing the 80-180 km/h sprint in 15.91s instead... [...]