[aerohead]

After reviewing the wind tunnel smoke-flow imaging videos for the Ioniq-6, I recommend NOT attempting to use this device.
The Ioniq-6 has turned out to be a 'silhouette' car, just like the 1968 PORSCHE 911 RS 2.7. It's designed for it's 'look', not aerodynamics.
And Hyundai's 'N' Division ( The AMG of Hyundai ), wishes to campaign the RN22e, Ioniq-6 race variant at the eTouring Car World Cup Race Series.
The Ioniq Hybrid has a 'better' roofline than the '6.'
Had the designer used the 2007 hybrid roofline, the '6' would have lower than Cd 0.21.
Hyundai wants to 'emotionalize' the car... make it 'fun to drive fast'... a 'showoff drift king', leaving consumer logic and reason at the door.