I am interested in the rear diffuser you built. Where did the inspiration come from regarding the design ? I have been pondering making one of my own and I was looking at the stock rear diffuser on the Nissan Leaf as a design-base.
Nissan Leaf stock rear diffuser
From what I understand, the efficiency of the rear diffuser is dependent on the air flow preceding it, hence the recommendation for smooth panels underneath the car; which you did !
