Congratiolation on your car,that's really amazing to look at , but are you make the whole car at onc mesh then you cut the parts out and split them , or you make like staring with the hood then working on the front bumpers like that , each one sepreat from the other from the start
I tend to build separate panels with gaps that I later extrude and chamfer to create door lines. That way I don't have to cut up a mesh to work in a door line or seam. If I create it as I go then mesh flow is less messy.
these are really excellent.. can you show us some wireframe views of this particular scene? w/ all the curves it would be really interesting to see how you built up your shapes.. and i love the clay shader you have going on.. almost has an AO effect