They might fit, I had 245's on my 17x9 rim. It kinda spread the tread out. They will be going on a 17x8" rim, right? Yeah, I have no real idea. Just trying to @ least get the discussion going!
a 215 section width tire would look very, very small on 17X8 wheels. 245/45/17 tires are not that expensive, and some guys even
squeeze a 275/40 on the rear.. a 215 is a size that a lot of honda/acura guys run on 17s, but it would look very stretched on a
8 inch wide wheel, and could even reduce traction compared to a 245.
i'm more concerned with the 40 profile than i am the 215 width, you're talking about using a tire that's 2" smaller than stock on the car, and that is just going to look all sorts of awful.