These are used to increase castor similar to an ALK or using forester bushes on a GC/GF chassis. Car feels flatter in the front end when cornering imo. These shims are 40x40x10mm with a 14mm hole in the center and mine were knocked up for $20 by a local engineer. See footnote about 10mm+ shims. You need 4 total, 2 for each side. All you need is: Jack Axle stands 1/2" Breaker bar or ratchet 19mm socket 1/2" extension 1) Jack the car up safely or however you like but dont blame me if