Regulator and return line ater the rails?
03-21-2010, 10:33 PM
#1
Regulator and return line ater the rails? I'm having a pressure drop when when using my N20. I think it might have to do with the noids acting like a dead head, once opened the fuel system takes a second to recoupe. This is causing an issue with my FPSS unless i set it really low.
Right now I have:
A single -8 coming out of the cell and splitting in to 2 lines going in to dual Walbro 255's. From there it goes back to a single -8 and to an adjustable regulator.
Out of the regultor:
-8 gets split and goes to the rails.
-6 returns to cell
I have a fuel noid off each rail right now for the 2-stage N20 kit.
while running the truck runs off 1 pump. When I arm either N20 system it starts the second pump.
Currently each stage has a small 100 jet in it.
When I have the truck off and arm either system, I have a solid 58psi as the pump is running constantly. When i hit the throttle switch, the pressure drops and the fuel pressure safety switch turns it off and on continusly. I dropped the FPSS out of the way and tried it. it's hit and miss on keeping pressure and not keeping pressure.
I'm thinking of changing the fuel system to:
Dedicated -8 feeds to each fuel pump.
-8 y after the fuel pumps
-8 splits and goes straight to the rails
On the other side of the rails each one gets a -6 T fitting. One side gets reduced to -4 and goes to the noids. The straight side goes back to the regulator.
The -6 return stays the same.
My thinking here is that the fuel system would then supply the N20 fuel before the return and have a better chance of keeping up on the initial hit (IE less fuel going to the return on the hit, vs moving it from the return to the noids like it is now)..
Is anyone doing this?
Right now I have:
A single -8 coming out of the cell and splitting in to 2 lines going in to dual Walbro 255's. From there it goes back to a single -8 and to an adjustable regulator.
Out of the regultor:
-8 gets split and goes to the rails.
-6 returns to cell
I have a fuel noid off each rail right now for the 2-stage N20 kit.
while running the truck runs off 1 pump. When I arm either N20 system it starts the second pump.
Currently each stage has a small 100 jet in it.
When I have the truck off and arm either system, I have a solid 58psi as the pump is running constantly. When i hit the throttle switch, the pressure drops and the fuel pressure safety switch turns it off and on continusly. I dropped the FPSS out of the way and tried it. it's hit and miss on keeping pressure and not keeping pressure.
I'm thinking of changing the fuel system to:
Dedicated -8 feeds to each fuel pump.
-8 y after the fuel pumps
-8 splits and goes straight to the rails
On the other side of the rails each one gets a -6 T fitting. One side gets reduced to -4 and goes to the noids. The straight side goes back to the regulator.
The -6 return stays the same.
My thinking here is that the fuel system would then supply the N20 fuel before the return and have a better chance of keeping up on the initial hit (IE less fuel going to the return on the hit, vs moving it from the return to the noids like it is now)..
Is anyone doing this?
03-22-2010, 03:09 PM
#3
That's what I was thinking.. The regulator is too slow to make up for it.
Nate, If I were to run a line from each rail back to the regulator, how small could I go? Could I go dual -4 in to the regulator (IE both ends of it) and a -6 return to the cell? Or do you think that would be too small and cuase pressure to creap up?
The single -6 return keeps up with both pumps on right now even with the truck not running.
So my question is would dual -4's move as much as a single -6?
Nate, If I were to run a line from each rail back to the regulator, how small could I go? Could I go dual -4 in to the regulator (IE both ends of it) and a -6 return to the cell? Or do you think that would be too small and cuase pressure to creap up?
The single -6 return keeps up with both pumps on right now even with the truck not running.
So my question is would dual -4's move as much as a single -6?
03-23-2010, 11:14 AM
#4
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Tech the same volume would pass but just to keep things moving smoothly I would just do -6. coming from -8 feed the volume you have to push through -4 could cause some pressure change. -6 is easier to come by the different fittings and easier to assemble and prob cheaper.
03-24-2010, 05:16 PM
#5
Thanks Nate.. I read this after I ordered -4 for the returns..
The new system will actually look like this:
Dual -8 from cell to dual filters then dual Walbro 255's
Y connector (dual -8 to single -8)
Single -8 up to the front and then splitting it dual to -8 in to the rails.
-4 out of the rails to a -4 T (both rails).
One side of the T goes to the fuel noids and the other goes to the regulator.
-6 back to the cell.
I'll hot wire both pump for testing purposes while the truck is off to make sure it doesn't push past my current 58psi. If by chance it does, I might bump the fuel pressure up a pinch as I am at 92-93% injector duty with the current 36's.
Thanks again for the help Nate..
The new system will actually look like this:
Dual -8 from cell to dual filters then dual Walbro 255's
Y connector (dual -8 to single -8)
Single -8 up to the front and then splitting it dual to -8 in to the rails.
-4 out of the rails to a -4 T (both rails).
One side of the T goes to the fuel noids and the other goes to the regulator.
-6 back to the cell.
I'll hot wire both pump for testing purposes while the truck is off to make sure it doesn't push past my current 58psi. If by chance it does, I might bump the fuel pressure up a pinch as I am at 92-93% injector duty with the current 36's.
Thanks again for the help Nate..