Hello jp, You mean something like a joyride for one day or do you just want to rent a fast car for a couple of day?

Here is some (possibly sobering and probably late) advice: many stretches of the autobahn have a speeding restriction (120km/h, about 80 mph) and that for very good reason. Other areas certainly have not but I would strongly caution you about going very fast (>100mph or >160km/h) if you are not used to those kinds of speed - it is very hard to imagine the forces that pull a car in any direction when you are going that fast and a tiny mistake will send you off the road or into another car, certainly fatal at that speed. If you have to step on the breaks the car very hard will be very hard to control. If I have not scared you off then make sure you get a car that has stability control (any Mercedes, BMW, Audi) as those can help a bit. Good luck and be safe!

Sixt is a car rental company in Germany where their rental cars are more often than not Mercedes and BMW.

http://www.sixt.com/

nie wynajmuj od Turków - najlepiej od razu na lotnisku coś wybierz.

niestety niektórzy są tam nieuczciwi (właśnie ja się spotkałem z nieuczciwymi Turkami).

Tip 1: Drive on sundays, if you have a need for speed. On that day the LKWs (Trucks) aren't allowed to drive on the Autobahn.

Tip 2: Drive at night, there are a lot less cars on the road.

Tip 3: Drive reasonable. Even if there's no tempo limit, it won't do you any good if you run into a family van, most likely killing the family therein, if not you as well. If you have any doubt whatsoever, hit the breaks, but keep in mind there might be someone behind you.

Tip 4: Here you have an overview of the Autobahnen (plural of Autobahn). It does not include the speed limitations, but the average daily traffic. You should probably limit yourself to green areas. http://www.autobahnatlas-online.de/index_e.html