Hi Guys

I have a V5 STi with original 16 x 7 rims. I am thinking of getting an Ultrex set which are 18 x 8. My concern is that the larger rims and tyres could affect the drivability of the car (eg. even as far as giving incorrect speedo readings).

Would appreciate any insight / guidance you could give as to what i should look out for.

Thanks in advance......