Hello,

I ordered for my RX-8 the Michelin Pilot Alpin 225/40R18.

I'm not a tire GURU, did I ordered the right size ? I'm just concerned about the 40 instead of 45...!

Thanks

Simon.

Hey there,

Go here:

http://www.1010tires.com/tiresizecalculator.asp

and punch in your OEM tire size (225/45R18) and your Pilot size.

You can see all the stats on the differences.

I think canzoomer got a similar ratio in a 17" tire... you could ask him if he has any problems with a >3% diameter difference.