It won't fit. While you're only talking just over 3/4" wider, the overall tire diameter would be about an inch larger.
It would still be taller and may not look right. The 40 is the size of the sidewall. It's called an aspect ratio, and means the sidewall is 40% of the width. Check out tirerack.com. They have information on how to properly upsize wheels and tires. Even though the tire you spec'd may fit the wheel, it may not fit the car.
I've been running 235 - 35- 19" on the front of my car (2003 360). They are after market wheels but the offset is very little to the outside. The car is lowered, the fenders rolled and I do have some rub issues. Almost never an issue while driving only when turning into a upgraded entry like a steep drive or a large bump at speed. However it is only on the driver side and I can easily correct that with a coil spring adjustment. FWIW just wanted to pass the info along. I agree that the 255s would not work. Image Unavailable, Please Login
It’s a set of take offs for $450 so that’s why I’m tempted especially since I run Nittos comp tire and had to drive over the grapevine last month in the snow.
I have 245/35/19 fronts using Novitec wheels and Novitec coil overs on my 360. I'm sure that without the Novitec shocks there would be rubbing.
I tried to run 255/35/19's Cup 2's but they could barely turn without rubbing the fender liner. My friend has a 430 Scud and runs 255's no problem, not sure if they have a fender liner in those cars. I ended up going 235/35/19 and it works great, no rubbing.