Kind of, yes. :) We use reference photos, preferably blueprints which contain exact measurements as background images in our work environemnt. Then, depending on your program and modeling style, you will either build curves to create lofts/sweeps of particular parts, or you would use primitives and start poly editing that to match the images, or you would use metaballs and hope for the best. The more accurate the references the better and also, refs from different angles beyond the top, side, front and back that a blueprint would have also helps you catch subtle nuances.