Thunder Lane builds hand-assembled, bespoke-valved suspension for Porsche — currently the 996-generation 911 (1999–2004, including Carrera 4) with the TL-ONE single-adjustable coilover system, and the 991/992 911 (2WD and 4WD, including Carrera S) with the TL-HAS height-adjustable spring kit that lowers the car while keeping PASM and the factory dampers fully active. The 911's rear-biased weight distribution rewards damping that controls platform motion precisely without going harsh, and every kit here is valved around exactly that balance.
Every coilover is built to order in Poland with 46mm electroplated, fully rebuildable monotube dampers and ships with CVP and PVP dyno graphs documenting how your set was valved. Spring rates are finalized with you before production begins, and every kit can be valved for street use, track duty, or both. Lead time is 4–6 weeks. Not sure between springs and coilovers? Read Coilovers vs Height-Adjustable Springs or the Porsche 911 (996) buying guide.