The standard fuel pressure regulator screws into the fuel rail at one end. On the 185 rail it's at the end nearest the fuel filter, on the 205 it's at the cambelt end. (you'll have the fuel rail for the engine fitted with 205 injectors). It looks a bit like the startship enterprise with a big round dish on top.
This is unscrewed, and a fitting is put in it's place to allow a pipe up to the aftermarket FPR. The thread for the fitting is the same as the others in the fuel system of M12x1.25mm.
The fensport kit comes complete with a banjo fitting with an exit for a pipe, or you can just use a straight screw in fitting with pipe outlet.
e.g.
http://www.ebay.co.uk/itm/Turbocharger- ... 1e6cebd5e7
The other large end of the FPR plumbs back to the return pipe you just removed from the standard FPR.
There is also a small vac. hose which comes from the manifold to the top of the standard FPR. This must be plumbed to the control input of the new FPR.
The FPR is effectively a pressure relief valve. When the fuel rail pressure exceeds the pre-set pressure, the valve opens and bleeds the excess back to the tank. The pressure is set by a combination of the adjustment and the vac pressure, so that a constant pressure is maintained across the injectors.
If you're stuck I have a spare filter to rail hose with banjo that may be persuaded to work, plus I'll be in Weymouth this evening.
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