I was hoping some one can help me. I just bought some 18in rims with 215/35-18s. I currently have stock 16in with 195/55-16's. They are close enough in width, but I notice that the 18's are about 1in smaller height wise. What tire should I put on to make it the same diameter. I was thinking 215/40-18. Thoughts?

 

a 215/35/18 is only .5" smaller then a 195/55/16, not really a problem.

Stock ride height? since the tires are already on there you might want to try them for a week with the 35 series and see how they are in terms of ride comfort and fit.

 

actually I can't run them yet, two of the tires are bad. The rims are fine. So I have to get at least 2 new tires anyway.

 

195/55-16 has a tire diameter of 24.4"

You want to get as close to 24.4" or slightly less. Larger tire diameter would give you less wheel clearance and a higher overall ride height which would increase center of gravity, not good for handling and cornering. A little over like 24.8" would still work.

For an 18" rim assuming 7" width, you did not mention what width you bought nor the wheel offset measured in mm.

215/35-18 fits rims 7-8.5" wide, tire diameter of 23.9"
215/40-18 fits rims 7-8.5" wide, tire diameter of 24.8"

205/40-18 fits rims 7-8" wide, tire diameter of 24.5"

235/35-18 fits rims 8-9.5" wide, tire diameter of 24.5"
245/35-18 fits rims 8-9.5" wide, tire diameter of 24.8"

Stock tire size for MINIs using 18" is
204/40-18
easy fit tire for MINIs would be
215/35-18 but you get a stiff sidewall and rougher ride over bumpy streets and potholes.
If your roads are poor then choose a 40 series tire sidewall.
Wider tires will often cost more and weigh more.

Don't mix and match your tires- what are your two tires? Worth getting four new tires.

For a Max summer tire consider
http://www.tirerack.com/tires/tires....DWXL&tab=Specs
$166 each 340 treadwear

For Ultra High Perf All Season tires (for cold weather and light snow)
http://www.tirerack.com/tires/tires....WSXL&tab=Specs
$145 each, 540 treadwear

 

thank you for the help. i see four new tires in my future.

 

I use 215/40-18 on my 2006 MCS with 18x7 wheels. Stock was 205/40-18.
I have no problems with the 215 verse the 205.

 

will definitely be going with 215/40-18. Not sure of offset, but rims are 18x7.5.

 

Post up pics when you get them mounted up, thanks!

 

Finally mounted the wheels and tires.
Before

After