Catalyst question.

[Klurax]

That you get a 18k euro's fine in Sweden is a myth, all you have to do is re-do the MOT if a cop notice you haven't got one (The emission test) and it cost like 320 SEK. All cars from -89 needs to have a cat fitted by law but there is cars before -89 that got cat fitted from factory and you need to keep it. If you move into Sweden and take your car with you aka "flyttgods" your car won't have any laws about the emissions, lights etc. because it was "road legal" in the state or country you moved from. So many american cars in Sweden don't have any strict emission test to pass so you can tune it without any problems.

Edit: I'd like to add that all cars pre -75 have no emission test at all to pass in MOT and between -75 and -89 they would only measure the CO and needs to be max 4.5%.