Not quite.
You can take a look few pages behind, there is a list of all the connection already used and a list of all the cars.
To give you an idea, you can use easy ones (same manufacturer, same name, same country, same designer, both v12, etc) but there are very few left, or more accurate and original ones.
In any case the connection has to define the car in a certain way, you can't use 2 cars owned by your neighbour or 2 cars available for sale on ebay at the same price, but you can use 2 cars owned by the same pilot or by a famous person or 2 cars that were for sale at the same price from the beginning.
Take a look around, it won't take much.
Always keep in mind that it's a game and only points are at stake here, that's why I wouldn't be too strict.
Last thing: only cars...I would like to avoid buses,trucks, airplanes etc.
