[s2man]

I want to clean up the rear end of my car. Aerodynamically, that is. It's got a nice start on a boat tail, but everything is rounded off. I want to add a small lip to get clean air-flow separation. I'm looking for a small wedge-shaped cross section. Maybe 3/4" x 1/4", or a bit larger. Rubber, silicon, or soft plastic would be fine. Has anyone seen a product I could use for this?

I've looked at all the molding, seals and weather stripping at the hardware store and Home Depot. Weather stripping usually has a square cross section, and the other seals usually wrap *around* something. There's got to be some application out there that uses a long rubber wedge for a seal. Thanks in advance.