see now that to mee looks like it would almost cause lift... forcing air that that has to go under the spoiler to go down more. Hard to explain, but in my head that looks like a reverse wedges shape, which would cause lift, like an airplane wing.
-Ed
YOu beat me with more pics, the second batch sounds more of like what i'm designing, fromt the lower front lip, back to the cross support, then from there back to the tranny tunnel.