This might help you to choose, posted by Sunbeamsam ages ago
http://www.alloywheels.com/tyrecalc.asp
Try typing 'Tyres' into the search function at the top of the page and see what pops up. Best to search just in the topics as there will be quite a few hits:I
where are you in the boro? house number ect.....how many pets?...te-he
Don't worry Matt i'm not a stalker, i was merely asking as i also used to live in Peterborough. For the record though, number 93 in Bretton and i have 4 pets!
195/50's do fit if it's a low profile that you're after. Rolling radius will be considerably smaller than the stock tyre size (which I don't the size of to hand).