4. Mercedes 190 AMG
Even though Mercedes asked Cosworth to design and engineer their famous 190 2.3 16V model, sparking the fierce DTM racing wars, AMG was behind most racing teams. By the mid-80s, AMG had a close relationship with the Mercedes top brass. This meant the Mercedes managers could depend on the AMG team to do some specific and sensitive tasks.
Since Mercedes had a racing ban and DTM championship was extremely important to the factory, AMG jumped in to lead the team. They prepared the cars and provided support for other private racing teams that used Mercedes products. Of course, AMG was too proud not to introduce the package for the Cosworth 190 2.5 16V model and that version produced 30 HP more.