Whats the deal with hooking up two Bosch fuel pumps in-line with each other?

To me it makes no sense, first of all you have the stock pump pulling fuel out of the tank and sending it to the first pump....then the fuel has to go through another pump to finally get to the fuel rail?



Whats the advantage? The pumps can only put up so much fuel pressure and can only flow so much fuel!

Why does having 2 in-line with one another matter?







Or am I completly missing the point.

i think it has to do with fuel starvation? making sure the engine has constant fuel supply at decent times...



or are you talking about a fuel pressure regulator?

I heard that they use the frist pump kinda like a priming system for the 2nd pump. I to would like to know the complete awser to this one..... https://www.nopistons.com/forums/pub...1047683561.gif

It kind of makes sense. Just think of the second pump as a booster pump for the first. Should work to keep up pressure in the line under any load, up to the pumps rated flow. Of course, the same thing could be achieved with properly sized fuel line and a pump sufficient to supply the engine.

i dont really get it either, but every german car is like that. prolly just cause its more money

LOL so thats why VW's and Audi's are so expensive....





Say I mount one of these in-line Bosch pumps closer to the engine like on the fire wall or where the stock fuel filter is on the FC's (close to the starter), and use the stock N/A fuel pump as a booster pump?

You think it would be alright?

Pumps push better than they pull. Mount it as close to the tank as possible.

Ok....but thats the whole point of the booster pump. Get the fuel to the Bosch pump up near the fuel rail......

Kinda like if ya look at the crapy MSD fuel pumps on ebay. They were ment to be a "booster pump" for the stock one in the tank... The MSD pump are ment to be mounted lower then the fuel and close to the tank...