It is an important aspect of wings that drag never goes away as the angle of attack increases contrary to the property of lift, or downforce in the case of the Sprint Car wing. We see in the chart that as the angle of attack is increased, the lift increases to a point. Once the angle becomes critical, lift falls off dramatically and drag continues to increase. High wing angles many times cause very little lift and a lot of drag. This contributes to high amounts of load transfer from front to rear and is often mistaken for added downforce. Load transfer to the rear tires does increase traction in the rear to promote bite off the corners under acceleration. This is useful for dry and slick conditions, but don't mistake downforce for load transfer.