450 WHP from the 1.6L ? B16 ? Dyno proven?
Need to see pics / videos asap! Any links to share? Once fully aero-modded you are going to have a real highway monster.
That kam-back is looking good! Any pics of the bare frame? I see your challenge on the side angles. I think a lot of your problems might be aided by just shortening the overall kamm length. That's quite a commitment as you have it now. I think you'd get a large % of the potential gains even if it were 1-2 ft shorter.... no?
Also kind of looks like you need another hard break on the sides. If you keep the angle between panels low enough, separation on the rear piece shouldn't be tooo bad.
I decided to sketch it:
