why can companys create exact replicas of cars (kit cars) without getting sued.?

Answer 1

They are NOT exact replica's. The shapes may be similar, but the internals are completely different.

For example, Factory Five, one of the biggest repliCAR companies in the US, has their flagship product a replica of the old Shelby Cobras. However, they use completely new engines, and don't use either the word Shelby or Cobra (both are trademarked) in their names and descriptions. Thus, neither Shelby nor Ford can do anything about them.

Answer 2

I don't see many kit cars around anymore, what are you talking about?