Your trunk lid looks like a fine example of quality craftsmanship. But I would have had mounted the scoop facing back, not forward. I would figure, hot air would escape out the top and go toward the back of the car like the stock vents behave. Maybe even a negative air pressure back there would form and actually draw the hot air out the top at higher speeds.
It would be interesting to hear the outcome. Tape tissue paper at the opening to see if the stringers get sucked in or blow outward. And while you're at it, tape some stringers to the stock vents too.
Not being a critic here, just sharing thoughts on all these neat things you guys come up with.
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Ron Dittmer - Driving A Mint 88GT, Automatic, Medium Red Metallic, Gray Interior, Black Lace Wheels, With Sunroof and Wing, in the Chicago area.