how big can i go on wheels on my '90 323 without messing up the speedo?

 

I have 17"x7" wheels with 205/40/17 tires, and the speedo seems to be right on with the cops radar (I just got pulled over this weekend).

I don't know if you're be able to fit much bigger than that... They look huge as it is

 

cool, sounds good to me i was thinking some adr sokudo's gunmetal of course on my red 323.

 

I was thinking to put some 15 inch rims on my 323, but I know that the biggest that should fit would be 18.
I am gonna paint them black or white
bruce