Pulse fittings?

[IceRocket1286]

so I know the intake manifold on an engin has a pulse fitting on it, but what exactly does it do? What does it do when you add a 2nd pulse fitting, say yoy added some spacers like TBM sells? i was just thinking about this today and wanted to know

 

[robertg]

Your fuel pump works off pulses from the engine. If you add another carb you need another pulse line. Some dual carb applications have only one fuel pump so you need only one pulse line.

 

[Mile9c1]

The dual OEM 38's only use 1 fuel pump, but the 44's use two. You can run dual 44's off a single external pump, if you want to.