1984 – 1987 Turbo Buick Adjustable Fuel Pressure Regulator. This kit replaces your factory, non-adjustable fuel pressure regulator with a fully adjustable piece. Now you can fine tune fuel pressure for maximum engine power output and performance. All 100% billet construction This regulator features a Viton 3-layer diaphragm rated at 100 psi constant and 300 psi burst. It is totally adjustable from 30 psi to 100 psi. Like our previous design, it also has a separate port for the vacuum line. This allows for easier adjustment without having to remove your vacuum line each time. It is a direct bolt-in replacement for your stock regulator. By installing an adjustable fuel pressure regulator, it will enable you to tune your car to the way you want it to respond.