After alot of research I think I've come to a conclusion that I'm going with slightly wider tires on my X coupe. I just want to verify with someone that the Hankook Ventus S1 Noble2 Performance Radial Tire - 245/45R18 100W will fit on my stock 18s. I couldn't find a definitive answer and just want to double check they'll fit before buying. thanks

 

Your OEM wheels are 18x8, the 245/45/18 will work just fine, but that is the widest tire you should use on that width.

 

is it safe to run the 225/50zr18 in the front and the 245/45/18 in the rear?

 

You can, it's about a .66% variance front to back (with the back being smaller), you want to keep that under 1%. Keep in mind that the rears typically wear faster so that variance will increase over time, but shouldn't get to the 1% point.
Use this calculator when trying new setups
https://www.myg37.com/forums/tire_rim_calculator.php

 

thanks blnewt. you're the man

 

Did you look at toyo proxes t