Long-time lurker here, and I wanted to give back some potentially useful information. I spent a lot of time looking for details on a 17" winter setup on this forum and elsewhere. Tirerack.com gave me absolutely no information, as they seem to have no data on the 2018 Elantra GT Sport (I still don't understand this. Get your shit together TireRack.). Combining the info I got from here, wheel-size.com, and a little info from discounttire.com, I eventually took the risk of telling Tirerack I had a 2019 Elantra GT N-Line, and ordered a wheel and tire package.
Why TireRack and not DiscountTire? DiscountTire charged $60 per TPMS sensor vs. Tirerack's $48, and also would not send the wheel/tire package to my house; instead only offering me an appointment time where I'm assuming I would have had to argue with them and tell them to just put the mounted wheels and tires into my wife's SUV (which in and of itself would have been a huge hassle: my wife doesn't drive my car, and we work totally different schedules.). Also, when I decided on a combo and got them from my shopping cart into the payment section with all the shipping and taxes added in, TireRack ended up being a little cheaper (even with cheaper and potentially crappier wheels from DiscountTire).
DiscountTire did offer a wider variety of wheels, including some bronze options which were tempting, but as my buddy advised, bronze probably would have clashed with all of the chrome around the windows and on the grille. Also, I wasn't sure about the quality of the Drag and Focal brands. By the way, if anyone has any good inexpensive methods of de-chrome-ifying my car, I'd love to see them. I've only recently realized just how much chrome there is around the windows, grille, headlights, etc... So much chrome; I look like an old guy. I mean... I am an old guy but shit...
I eventually decided on some Enkei Performance PX-10's in 17x7.5 +40mm with 225/45R17 Continental VikingContact 7's. The wheels and tires stick out a bit farther than the OEMs, and apparently, according to wheel-size.com, the scrub radius is 14mm farther towards positive (doesn't seem to make a significant difference..?).
Now the information I was really worried about: The wheels clear the brake calipers with no problem. There's enough space in between that makes me think that even a 16" wheel could work. I'll try to get some precise measurements at some point and add them to this thread. The TPMS sensors worked fine, without any kind of tool (screw DiscountTire for trying to get customers to pay multiple hundreds of dollars for a TPMS tool, when one is not needed). I just put the new wheels on, drove the car for a couple miles, and the sensors picked up the pressures and displayed them on the info screen between the tach and speedo.
TireRack inflated the tires to about 36 psi, BTW. Also, they sent a new set of super shiny chrome lug nuts (packaged within one of the wheels very securely) which have correct tapers for the new wheels. They also idiot-proof the wheels and tires by providing stickers that tell you driver side and passenger side, in case you have directional tires and are somehow unable to read the direction markers on your tires.
I've attached pictures. Will add more in a few days.
Sorry for the really long post, but I wanted to include every bit of potentially useful information.
P.S. - Who else thinks the oil drain plug should be on the back and not the front of the oil pan? I mean, come on Hyundai, that's backwards.