I've run 225 on stock 16s for 8 years. I have run 225/50 on road tyres and 225/45 on race tyres. I think the reason I started down the /50 road rather than /45 was due to having better variety at the /50 (for road cars anyway; certain race tyres aren't even offered in 225/50) so I've kinda stuck with it.

Remember, the second number (205/50) is the tyre's height as a percentage of the tyre width, not the tyre height in mm. Therefore a 225/50 will be taller than a 205/50, not the same.

Heights:
205/50 = 102.5mm
225/45 = 101.25mm
225/50 = 112.5mm

Tyre's outer circumference (for 16" wheels):
205/50 = 1920.8mm — this is the base number
225/45 = 1912.9mm — this smaller circumference will result in a +0.41% difference in speedo reading; speedo reads over, so when actually traveling at 100km/h your speedo will read about 100.4km/h
225/50 = 1983.6mm — this larger circumference will result in a -3.17% difference in speedo reading; speedo reads under, so when actually traveling at 100km/h your speedo will read just under 97km/h

…I think.

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[COLOR="Blue"]"Your car positioning and awareness is f*ing bang on. And like, every single time.
In terms of getting that close to the bollards, Ive only been with one other person that can drive like that" –Franz[/COLOR]
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