Low level - 155,000 faces. 1 iliteration of meshsmooth
Medium level - 365,000 faces. 2 illiterations of meshsmooth
High level - 975,000 faces. The only difference between medium and high levels is that the high level contains 3 dimensional tire treads, while the the medium level uses a displacement map. (almost unnoticeable in most renders, but the 3d treads look amazing in close ups)
All meshsmooth is kept intact so you can alter it any way you like. The file is grouped into major parts to allow for easier manipulation of the scene.