I have been looking for new wheels since putting air ride on and think Im going with the xxr 521 gunmetal 18s. I have new 225/40/18 falken tires now that I plan to use if possible. They come in 18x8.5 with +25 or +35 offset and 18x10" with +25 offset. If I went with 8.5" +35, would the 225/40/18 fit good or should I go with 215/35? I don't know about the 18x10 +25 for the rear?

 

The 18x10 +25mm in the rear will take some work to fit. The tire should work well, but a 215/40R18 would be more optimal. With the 225/40R18 you'll be sitting the fender on the tire. Hell, with an 18x10 +25mm you'll probably be hitting the tire on the fender quire regularly.
The 18x8.5 +35mm will work fine in the front. You can certainly use the 225/40R18 up there. Fender liner will probably need flipped and you can physically pull on the fender a little. Just be careful.