Hi all, can anyone tell me what the largest size rim/tire/width combo I can install on a 79 coupe deville without modifying the wheel well of lift, i'm thinking 18s or 20s. However I may install air bag suspension, any help appreciated, thanks.

 

I am currently running 20 inch Dayton 150's on my '78 Coupe DeVille. I can get some pictures and more info off the tires if you like.