What Is a Neuron? Diagrams, Types, Function, and More Manley Nissan (SR20DE SR20DET) 16pc Titanium Retainers. Upgrade your valve train with Manley Performance Titanium Retainers and other lightweight titanium options designed specifically for high revving sport compact engines. Machined from aerospace grade heat treated 6AL 4V titanium, these retainers dramatically reduce valvetrain mass for quicker rev up, improved valve control and enhanced overall responsiveness. The reduced weight helps your engine hold spring pressure at high RPM, minimizing float and unlocking more performance potential in race or aggressive street applications. Lightweight, strong, and precision built for serious performance. This Part Fits: Year Make Model Submodel 1991 1996,1999 2002 INFINITI G20 Base 1994 1996,1999 2002 INFINITI G20 T 1995 1998 Nissan 200SX SE R 1991 1993,1995 1998 Nissan 240SX Base 1991 1992,1997 1998 Nissan 240SX LE 1989 1998 Nissan 240SX SE 1989 1990 Nissan 240SX XE 1991 1993 Nissan NX SE 1991 1993 Nissan NX XE 1991 1994 Nissan Sentra SE R