Ni5mo180SX

Does the T2 have a variable fuel pressure system based on boost which increases pressure from approx 40 to 110+psi under full boost? If so, would this make a mechanically controlled fuel pressure regulator incompatible with the system?? Thanks.

NZConvertible

All EFI cars vary fuel pressure according to manifold pressure. The fuel pressure regulator uses a hose connected to the manifold to keep fuel pressure at a set amount above manifold pressure. In the case of the FC this is ~38psi, so whatever the manifold vacuum is, add 38 to it and that should be the fuel pressure. Turbos work in exactly the same way, but their fuel pressure goes higher because the manifold pressure goes higher.
It should never get to 110psi, because the pump can't even get close to that. It's max output pressure (before the FPR) is about 70psi.

Ni5mo180SX

Thanks a lot for clearing that up. So would I be able to use a mechanically adjustible FPR?? I was told that it would let fuel pressure go up too much?? The unit is a Sard Type S listed in my sig. It also has a tee in for the manifold. Thanks again.

NZConvertible

Being adjustable, you can set it to whatever pressure you need. This is best done on a dyno, because increasing fuel pressure without any control changes could result in overly rich mixtures.