The model was created for a friend who is building a 1/5th scale model of an old motorcycle that he used to race. A scaled down version of the carb was created using a rapid prototyping machine.
The detail level is just enough to create smooth surfaces, but not so high that it would tax your scene.
The model is simply a polygonal mesh, untextured, no UV mapping. It's also important to note that there are no internal parts. The model was created as a solid to be viewed from the outside only.
The .3ds and .stl formats are triangulated, but that is to be expected.