here you go before you spend a lot of money on spacers, adapters, wheels and tires. check out these to sites first
http://www.willtheyfit.com/
http://www.tyrestretch.com/index.php
i hope this helps in finding your answers. messing around with the numbers on the first site looks like 195/40/18 looks good on both size rims.



If youre runnin spacers use above info.