I was looking at the "unique spoiler", and if you said with cfd it showed a net gain of about 2%... I wonder how much better (if any) it would do if there was a second spoiler inverted and added to the bottom bumper. The lift/downforce would offset each other, so you could shape the lower one different to keep the downforce if that's desired. Either way, you might be in the 4 or 5% gain area. In practice, these could be added to the sides of the car also to help just a little more (unless they blocked the brake lights too much). Something to think about.
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