Any consensus on the best tire size for the GS 430 18" wheel upgrade? Recommendations will be greatly appreciated.

 

Use this calculator to help you determine the "proper" size. How you deviate from the "proper" size is completely up to your own personal reasons. I chose a larger size as my "best tire size" for my own reasons. YMMV.

http://www.miata.net/garage/tirecalc.html

 

Thank you Flop. How is the ride and do you have any rub issues with your 235/50's? Thanks so much for your feedback.

 

I have no rubbing problems. The ride is firm but that is not the fault of the tires. It is because I am lowered.

With stock suspension, IMHO your best bet with the GS430 wheels is 225/45-18.

 

Thanks much again Flop. My concern is that the 225/45-18 's wont really look right unless the car is lowered (excessive wheel well gap). My goal is to get a good look, fill as much of the well as possible, and not lower the car. From what I read it looks like that may require 225/50-18 or 235/50-18. Do you think either of the latter will look OK without lowering springs?

Thanks again for all your help.

 

No it won't look as good as you want, although it will look better than stock. Search for and read my thread titled "Lowered TCH" where I've included photos of the non-lowered car with my GS430 wheels and tires.