I've been trying to decide on a fix for the gasoline smell that is evident when I am driving my 818S. I suppose that it is caused by the flat rear bumper and rear (small wing) on the car making the air/exhaust smell waft back into the cabin. The last convertible that I owned used a screen behind the seats to keep air from hitting you in the back of the head. Anybody come up with a solution for the 818? Also, I am wondering if my custom engine tune is richening the fuel mixture enough to cause more gas smell.