I bought a set of RIAL x10 5x19" for my audi a8. I did not now are they how convex from pictures but they looked nice.
When I got them I started to think how to make them more aerodynamic.
I decided to make some custom 1mm thick aluminium block plates to them. First draw the basic shape with 3d engineering program then print the shape to paper and cut out.
as you can see it took mayny samples to get the shape perfect. Then I ordered a set of those and started bending them to correct shape. They fitted nicely.
Then I decided to paint them also green and bigger triangles to glossy black. Plates are glued from behind. Time will tell will they hold Glue hold 24 kg per cm2.
Finished wheel is looking sweet and the curvature is just perfect. Although this aint yet totally ready. It still needs Tuneko centercap sticker and few other final touches.