225/40/18 size tires on 18x7.5 rim sound ok? I see that size on a lot of the 18x8.5 tires-Too wide?

225 on 7.5 is perfect fit. I have Michellin Pilot Sport 225 on Volk TE-37 18x7.5

I had 225 40 18 S03's on my 18 X 7.5 Volk LE37T's... Perfect Fit!!! (BWW)
 

<img src="http://www.hostdub.com/albums/StLTurboA4/Volks_012.jpg">

It will cause the car to drift more easily
 

but it will make the ride a bit smoother.
I have 235x35R19 on my 9" wide wheels and it works nice for everyday driving but not for track

I was thinking that myself
 

At least it is for 17" rims'
and going to 8.5" rims to me does not give any protection to the rims.

i too have 225/40ZR18 on my 18x7.5 with a 40 and some 69... 24/7... 10-4. (theyre good)