ktmmike, welcome to the370z.com.
1. The 2014 370Z base still comes with 18" wheels. The sport package gives an upgrade to 19" wheels. Does the car on the lot have red brakes that say "NISSAN" on them? If so, it has the sport package.
2. The wheels are indeed interchangeable, with no modifications whatsoever. The only limitation with Sport package-equipped (the one with the big brakes) is that you CANNOT fit smaller than 18" wheels. Anything 18" or larger is fine.
3. The 350Z also had wheel options - a base 17" wheel with (I think) 6-7 spokes? And it had an optional 18" forged by Rays wheel option with 5 spokes.
4. I have seen 370z 19" wheels on a 350z before, and I thought it looked great.
5. I don't think there is a specific thread, but correct me if I'm wrong. All it boils down to is this:
US Spec 370z's from 2009-present can come optioned in 5 manners:
-Base
-Base+Sport
-Base+Touring
-Touring+Sport
-NISMO
The base and base+touring models have 18" wheels and smaller brakes. Any Z with the sport package will have larger brakes, and the 19" forged by Rays wheels.
The NISMO has it's own body kit, and NISMO branded 19" wheels that are wider than the Sport package 19" wheels.
If you want more info, don't hesitate to search, or if you can't find it, ask!
