No, this is not an acceptable swap.
Maybe, but it's quite a bit wider. Check for rubbing very carefully.
225/55R16
Yes, it can.
No, this is an unacceptable swap. If you wish to go to a 50 series tire you should install 225/50-16 which is and excellent swap.
what is the diameter difference from a 205/65/16 vs. 225/60/16
Can a 225/60R 16 tire replace a 235/70R 16 tire.
205/60-16 or 245/50-16. Either of these sizes is compatable with your 225/55-16.
Mazda RX-8
The OEM size is 205/70-15. But I assume you want to stay with a 16" tire. If that be the case a 205/65-16 is much closer to the OEM size than the 225 tire.
it will fit but the tire is wider and is taller in diameter. Your speedometer will be off.
yes it should work
I wouldn't, too much difference.