Indeed they're all ultrathin surfaces. I modelled everything myself. the logo and GT4 I drew in MicroStation (A kind of AutoCAD), with pictures from the internet as refrence. The license-plate I also drew in Microstation. I took all the dimensions from the license-plate of my own car (including all the nummbers, stars, letters etc..) Nevertheless, I'll keep in mind everything what is said about bumpmapping, who knows when it comes in handy.

A bump map on the license plate sounds like a good idea, but how do I do that ?

Yes I installed the 3.0.1 patch. I did some testing, and indeed the interpolation was causing the problem. If I put the reflection to zero the spots are also gone even with interpolation on. Thanks for all the input, Enjoy the weekend.

What do you mean with your last sentence (flat look)?

Alvast bedankt

Yes, I still have to fix the windows. Should the windows reflect all colors or just it's own color (like carpaint) ?

Those shaders you mentioned look very realistic. Maybe I'll buy them after some experimenting. Thanks for the help.