BMR 67-69 1st Gen F-Body Upper And Lower A-Arm Kit - RedCombine with BMR Lower A arms, and you get 4 additional degrees of positive caster (2 degree from the uppers and 2 degrees from the lowers), providing up to 6 degrees of total positive caster over stock. This gives you improved geometry and increased lateral grip during cornering situations. The upper arms also have revised cross shaft geometry and shorter overall length, requiring less shim stack to achieve negative camber on lowered cars, or race