The fuel system is one thing that's giving me problems at the moment. (A side effect of what began as a cooling problem). My Seven has a single high pressure fuel pump. The recirculate from the rail returned to a 3-port fuel filter mounted near the fuel tank (no return to the tank). The return line from the rail had a secondary aftermarket regulator installed in it. Unfortunately, that second regulator was installed backwards so there was no return flow at all and the 3-port filter is no substitute for a swirl pot anyway. Because of the high configuration of the Zetec's head cooling jacket and the relatively low radiator and reservoir tank there was an air bubble trapped in the head that caused a portion of the head to overheat and injector rail with it (since the fuel could not recirculate which would have otherwise kept the rail cool enough not to boil the volatiles in the gas). I've removed the air bubble in the head and the cooling is fine now. I'll eventually re-plumb the cooling system so that air cannot so easily become trapped in the high spots. I also need to re-plumb the fuel system, but for the time being it is enough to remove that secondary regulator. Does your Seven's fuel tank have a fuel return port? I'm thinking about making a sturdier stainless steel fuel tank with a dual pickup system to solve fuel starvation from lateral g-forces. The configuration of the fuel tank makes that redesign rather easy and although there's a weight penalty for SS over Al, the sturdier tank will be safer too plus only one fuel pump will be required and a swirl pot is unnecessary..... As far as fuel cells go, I am using two pump setup, one low pressure to a swerl pot and then a high pressure for the injectors...