Steve, the wings on these cars, and sprint cars make down force, helps push the car down, making more bite on the track,
like Indy cars, without the wings, it would not stay on the track , or go as fast,
A wingless sprint car will do a 3/8 dirt track in 13-14 sec. with the wing,,they turn lap times in the 12 sec 12.5 sec.
Its a fine art on how to set them up, and were, and how to install them. move it back, ya get more rear bite, move it forward
you get more bite on the front, side to side, you move the bite left to right,,
Hope this helps. ( put your hand flat out the window when driving, turn your hand up or down, the wind will push it down or up, thats down force, or up force,)