[wagonman76]

Today after work I did a tuft test. I removed the kamm base rods, then taped on 7 pieces of white yarn along the last 5 inches of the trunk lid. I could just barely see them out my rearview mirror so I took the wife with me about a mile down the road and back. Both there and back, the strands were wagging back and forth like a dog's tail.

So after we got back I got to do more on the kammback for a few hours. The pics show what I accomplished till I could not see anymore. I ended up just leaving the back bar at 6 1/2" high, it should still be a lot better than the current airflow. It is just tack welded but it is pretty rigid so far and is nice and light, weighs maybe 10 lbs. The only thing I might change is knock out the frontmost diagonal braces and replace them with pieces bent at the top so it more closely follows the c-pillar.

I am actually thinking more and more about leaving the extensions on the back and completing the boattail, that's why I haven't cut them off yet. It measures about 2 feet, which is just about the same as another sketch I drew (just a little bit shorter version of the one posted by testdrive). The bottom of my steel bumper has holes that I can use to bolt some angle iron to support the back end, and I can hinge it there. (I really would rather just hinge it on the rearmost anchor bolt rather than try to make it slide.) Over the 2 ft boattail the width of the car would taper in to meet the bars that currently extend out, which comes out to about 15 degrees per side.

Hope the weather stays decent, I want to keep working on this.