Fitment Question

I'm planning on getting wider tires for my 2015 Lancer. I wondered if 245/40r18 tires would look good on the car and if they wouldn't be too wide, the goal is for a flush setup. Also wondering if id gets any rub if I were to turn my wheel all the way.
Also wondering if I can have wider tires on my stock rims or if I'd need to get wheels as well.