How does fuel rail work?

[Wulfgang]

How does the fuel rail on the RB20DET work? My rail has what look like identical fuel regulators at each end. The front regulator has a vacuum line connected to the intake manifold, but the rear regulator has no vacuum hose attached.

Why the two regulators instead of one? Also, which one is the supply regulator and which is the return?

[BlockHead]

The one with the vacuum line is the regulator(the fuel send line goes there), the other without the vacuum line is a fuel dampener(fuel return line goes to that)

[Wulfgang]

If the fuel supply was fed to the regulator, wouldn't the pump sometimes deadhead (which is bad news for a positive displacement pump)? Shouldn't the pump be connected to the dampener and the return be taken from the outlet of the regulator (like it is on the KA)?

[BlockHead]

yeah your right I said it bass ackwards

[Wulfgang]

Ok, cool. It just looks a little weird to see a "regulator" (the dampener) with no vacuum line attached.

I just wanted to get this right since I have seen several people say that they got their fuel lines mixed up on the RB20's.