inline pump always on?
Mar 30, 2008 | 02:43 PM
#1
inline pump always on?
I'm trying to decide how to upgrade my fuel system and don't know the answer to some easy questions.
I'd like to add an inline pump to the existing system but don't really care for how loud they are. My first questions is if you place a pump in series with the factory one like most guys do (see below), is it always running or only under boost?
I'd like to add an inline pump to the existing system but don't really care for how loud they are. My first questions is if you place a pump in series with the factory one like most guys do (see below), is it always running or only under boost?
Mar 30, 2008 | 03:21 PM
#3
This is a return style fuel system. I guess the only way to have a second pump that is only on under boost is to go with a dual in-tank or possibly a parallel system rather than series?
Mar 30, 2008 | 03:40 PM
#4
Twin in-tank with a Hobbes switch will do it. I have twin 255's, the second one comes on a 4psi. I get almost 70 psi fuel pressure through the stock lines, crossover, and rails 
Mar 30, 2008 | 04:50 PM
#5
You could do a semi parallel system I think if you put a Y right after the fuel filter and then one into the pump and one into a check valve, so there is no way for the extra flow from the second pump could "push back" to the stock pump. then just have the external pump on a pressure switch to come on with boost. Should work as well as a series setup with the stock pump being the flow restriction, but with the pressure being divided between the two pumps when in boost, it would flow more then when the stock pump was carrying the system on its own. Just an idea.
Mar 30, 2008 | 05:00 PM
#6
Just asking here beacause I think it's relavant, doesn't the in-line pump NEED to be on or issues will arise?
If the in-line is off is there not a restriction pushing through it with a single in-tank stock pump? Just asking beacuse it has been explained this way in the past to me.
If the in-line is off is there not a restriction pushing through it with a single in-tank stock pump? Just asking beacuse it has been explained this way in the past to me.
Mar 30, 2008 | 05:30 PM
#7
I was having the same thought, except I think you would need a solenoid valve instead of a check valve.
Trending Topics
Mar 30, 2008 | 05:57 PM
#8
You could do a semi parallel system I think if you put a Y right after the fuel filter and then one into the pump and one into a check valve, so there is no way for the extra flow from the second pump could "push back" to the stock pump. then just have the external pump on a pressure switch to come on with boost. Should work as well as a series setup with the stock pump being the flow restriction, but with the pressure being divided between the two pumps when in boost, it would flow more then when the stock pump was carrying the system on its own. Just an idea.
Mar 30, 2008 | 05:59 PM
#9
Just asking here beacause I think it's relavant, doesn't the in-line pump NEED to be on or issues will arise?
If the in-line is off is there not a restriction pushing through it with a single in-tank stock pump? Just asking beacuse it has been explained this way in the past to me.
If the in-line is off is there not a restriction pushing through it with a single in-tank stock pump? Just asking beacuse it has been explained this way in the past to me.
Mar 30, 2008 | 06:00 PM
#10