can i put 18x9' steeda rims with out adapters

My advice would be to ask a tire shop, they deal every day with these type of issues, The rims might clear up and down but might be to wide for this model, just remember you will need to keep the overall height the same or you will throu off your gages. And the lower profile tires will take away from the ride comfort. Hope this helps and best of luck.

9" wide wheels are too wide...you probably won't clear the struts or the fenders in the rear, and the tires will rub with higher steering angles in the front (again, if they clear the struts). Make sure whatever you get is 5x108 bolt pattern, and about +42mm or so offset.