That would look like tractor

I'm not sure if you can get that size anyhow. (you can get 205/70/14 or 195/60/14. the nearest equivalent of a 205/70/14 would be 235/40/18 in diameter or a 195/60/14 would be 205/45/17, either one would be far to big without some mods)
If you tell me what size you have I can give you the equivalant tyre diameters to fit the car without messing up your readings.
Unfortunatly its not just a case of biggere/smaller rims = smaller/bigger profile. You have to take the width into account