The straight-8 cylinder engine of the 540K was fed by twin pressurized updraft carburetors and developed a natural 115 hp. However, there was an attached Roots supercharger (K) which could either be engaged manually, or automatically when the accelerator was pushed fully to the floor. This increased power to 180 hp. The top speed with the supercharger engaged was about 110 mph. The Sindelfingen factory employed about 1,500 people to build cars. This allowed a great deal of owner customization and a variety of 540Ks during the same model production/year.
I bought this one as a built model, but I took it apart,removed the chrome foil, re-foiled and detailed it when I put it back together.