Toyota Lexus fitted the 2011 2013 F-Sport with different springs, shocks and sway bars but I've never found any data on the topic about spring rates or damping rates for rebound or compression.

The base cars received different PN than those listed here. If anyone has any data on the topic I'd like to see it. Thanks!

Shock, Spring, Sway Bars 2011 - 2013 F-Sport IS250 - IS350 (some ISC and ISF parts overlap)
------------------------------------------------------------------
48231A SPRING, COIL, REAR RH
48231-53280 SUSPENSION-SPORTS&TIRE & DISC WHEEL-225/40R18+255/40R18, SUMMER TIRE, ALUMI
48231B SPRING, COIL, REAR LH
48231-53280 SUSPENSION-SPORTS&TIRE & DISC WHEEL-225/40R18+255/40R18, SUMMER TIRE, ALUMI
48530 ABSORBER ASSY, SHOCK, REAR RH
48530-80574 MARK 48530-53280, SUSPENSION-SPORTS&TIRE & DISC WHEEL-225/40R18+255/40R18, SUMMER TIRE, ALUMI 1
48540 ABSORBER ASSY, SHOCK, REAR LH
48530-80574 MARK 48530-53280, SUSPENSION-SPORTS&TIRE & DISC WHEEL-225/40R18+255/40R18, SUMMER TIRE, ALUMI 1
48705 LINK SUB-ASSY, TOE CONTROL, RH
48705-30130 SUSPENSION-SPORTS 1 $59.03
48706B LINK SUB-ASSY, TOE CONTROL, LH
48706-30070 SUSPENSION-SPORTS 1 $59.03
48710A ARM ASSY, REAR SUSPENSION, NO.1 RH
48710-30220 SUSPENSION-SPORTS 1 $175.74
48720A ARM ASSY, REAR SUSPENSION, NO.1 LH
48710-30220 SUSPENSION-SPORTS 1 $175.74
48730F ARM ASSY, REAR SUSPENSION, NO.2 RH
48730-30130 SUSPENSION-SPORTS 1 $143.76
48740F ARM ASSY, REAR SUSPENSION, NO.2 LH
48740-30130 SUSPENSION-SPORTS 1 $143.76
48805 BAR SUB-ASSY, REAR STABILIZER
48812 BAR, STABILIZER, REAR
48812-53030 SUSPENSION-SPORTS, TYPE B:REFER ILLUST. 1 $151.39
48818 BUSH, STABILIZER, REAR
48818-30210 SUSPENSION-SPORTS, TYPE B:REFER ILLUST. 2 $18.27
48824R BRACKET, STABILIZER(FOR REAR)
48832-30060 SUSPENSION-SPORTS, TYPE B:REFER ILLUST. 2 $10.12
48131 SPRING, FRONT COIL, RH
48131-53340 SUSPENSION-SPORTS&TIRE & DISC WHEEL-225/40R18+255/40R18, SUMMER TIRE, ALUMI 1
48132 SPRING, FRONT COIL, LH
48131-53340 SUSPENSION-SPORTS&TIRE & DISC WHEEL-225/40R18+255/40R18, SUMMER TIRE, ALUMI 1
48510 ABSORBER ASSY, SHOCK, FRONT RH
48510-80539 MARK 48510-53260, SUSPENSION-SPORTS 1
48520 ABSORBER ASSY, SHOCK, FRONT LH
48520-59655 MARK 48520-53170, SUSPENSION-SPORTS 1
48811 BAR, STABILIZER, FRONT
48811-30661 SUSPENSION-SPORTS 1 $216.39