Porsche 918 2015 (Polygon mesh 3D model) is available on CGTrader for $20. Original author: Heisen3D. Specs: 1782967 polys, 979334 verts.
STL (Stereolithography, filesize: 85 MB), OBJ (OBJ, filesize: 140 MB), DAE (Collada, filesize: 273 MB), ABC (Alembic, filesize: 157 MB), BLEND (Blender, filesize: 152 MB), FBX (Autodesk FBX, filesize: 94.9 MB)