Eric the car guy has vidfeo detailing alot of the chassis differences ITR has compared to DC2 and DC4. In it he states ITR spoiler produces 30% more downforce on the rear.

Anyone know at what speed 30% more downforce is created though?

If so is there any technical publications on this?

 

Wouldn't it be 30% at all speeds? Seems like a trivial amount considering non-ITR models make very little downforce.

 

Downforce begins to be effective at 40mph and then goes up.