Nissan RB25 NEO beehive spring and titanium retainer kit to suit 6mm stem Ferrea valves (F1934P, F1936P)
86lb @ 37mm intake, 89lb @ 36.55mm exhaust. 22.85mm coil bind. Fit 1.5mm shim on top of factory spring base. Only to be selected when using Ferrea F1934P and F1936P RB25-Neo valve. Must use K10063 locks.