So far on the Internet is not the normal instructions for converting models from other games to the NFS5. For example, I have a Panamera in 3d max, but after a few manipulations, the output CRP file from Z-modeller turns weighing 60 meters, and when the game chose this car - the game crashes ... Anybody can give a step by step the envelope of the other games?

Ex: From Underground 2, GTA 4 or smth like it...

...rubbish...

wtf is this?

Well, you are saying that you have a car in 3dsMAX, so I am assuming it is high poly. Make sure your car is not at all high poly before you mod it into NFS5. The game only supports a particular polycount, unless you get the high poly patch, which still probably won't be able to run super high poy cars.