I am about to fit a set of DTH throttle bodies and will be using the standard Rover fuel rail. Why does the pressure regulator have a vaccum connector?. I also have a vaccum pipe connected to a plastic cylinder with an electrical plug which I think is a charcoal can for collecting fumes. Can I just remove the vaccum pipe? will petrol tank still be able to vent, breathe. Also the engine has a vaccum connection to a breather on the cam cover via a very small drilling, I have been advised to ignore this, however if I block this the crankcase will have no through flow of fresh air to rid it of blow by fumes, does it matter?