These Malpassi / FSE fuel pressure regulators are designed for use in EFI vehicles, both factory standard and modified. With this particular model, fuel pressure increases at the rate of 1:1 with manifold pressure (or boost) – same as your factory regulator. This means you will get the same fuel delivery curve as factory fuel pressure regulator, however base pressure is adjustable which it is not with factory regs. No re-tuning or re-chipping should be required.