Are you sure you have looked at the right car?
My car has no C-pillars, it's a convertible wich only kind of has B pillars and no spoiler.
Could you maybe have confused it with the MR2 MK-2?
Anyway, getting the flow to stick would siglificantly reduce the size of the low pressure area behind the car, wasting less energy in the wake.
Alternatively I would need to fabricate a kammback-extension over the engine bay to reduce the angle.
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