Developed by RCE for the new chassis GR STi, these springs we're desinged to optimize the car's handling by pairing the already effective factory dampers to a increased rate spring. These springs lower the car 5mm front and rear, and have a rate of 320lbs/in front/rear. These rates we're determined by testing to find optimal rates for the front as well as the GR's new rear suspension design which has a different motion ratio compared to the older chassis STi's. These also include new bump stops front/rear which actually increases bump travel over stock congiruation. Perfect for owners looking for superb daily driver ride quality, but increased rate springs to improve performance, and reduce the cars natural tedecny to understeer.