Changing tyre width/profile from run flats to 'normals'?

[Busterboo]

My SDrive35iS is on Bridgestone run flats - 225/40 R18 88W front & 255/35 R18 90W rear.

If I change to (non-run-flat) Michelin PS3 (or 4?), should I change tyre width & profile?

 

[sars]

My SDrive35iS is on Bridgestone run flats - 225/40 R18 88W front & 255/35 R18 90W rear.

If I change to (non-run-flat) Michelin PS3 (or 4?), should I change tyre width & profile?

There is no reason too, if you decide to go up in width to 235/40/18's and 265/35/18's the overall diameter will go up by 8.0mm front and 7.0 mm on the rear this will mean a more accurate speedometer but less acceleration and worse fuel economy. If you want to increase rim size to 19" then correct size is 225/35/19 front and 255/30/19 rear

 

[Busterboo]

Thank you.