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Fuel System Routing

  • Thread starter Thread starter tannerc91gt
  • Start date Start date Apr 10, 2014

tannerc91gt

This last 25% is foreign territory at this point
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#1
  • Apr 10, 2014
  • #1
I'm building a RETURN style fuel system for my car.
There's a good chance I'm overthinking things as all 3 of these setups have been done.
Just looking for opinions as to which will be the most efficient way to route it. It consists of an In-line pump, with a filter before and after, into a regulator and then to my edelbrock fuel rails. System will be run at 58 psi.


This mounts the regulator next to the pump in the rear. Then the regulated 58psi travels to the passenger side rail, and around to the drivers rail in series. Feed line can enter at front or rear, on either side, that's irrelevant to me. To me this keeps the return fuel from traveling I to the hot engine bay before returning to the tank. Which is definitely good. But the only concern is a drop in PSI to the rail. Obviously this can be checked once built, just a matter of building it right the first time.


Same rear mounted regulator (stock configuration) but the feed line goes to a y block and to the rails in parallel.

Aeromotive was suggesting something more like this. I just don't see the need to tie the rails together in the rear?

This option runs the feed line to the return line mounted in the engine bay. Return line runs all the way back to the tank. Then the rails run in series (could do parallel here as well).

Again, probably overthinking things. Option A Is the leading candidate for simplicity's sake. Just want to hear some others weigh in.
 

hoopty5.0

mechanicus terribilis
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#2
  • Apr 10, 2014
  • #2
6 in one hand and half dozen in another?

I really don't know, Im interested to see if regulator placement matters.
 

90lxcoupe

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#3
  • Apr 10, 2014
  • #3
Regulator should be after the fuel rail or you could have issues burning fuel pumps up. I dont see any one setup up there i would run.

I did the tried and true, -8 feed to a y block, two -8 lines to the back of the fuel rails, then two -6 returns to the regulator, and a -6 line out of the regulator back to the tank.
 
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RacEoHolic330

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#4
  • Apr 10, 2014
  • #4
I wouldn't run any of the above setups either. I agree that the regulator should be downstream of the rails on the return side of the system. I also don't like creating dead ends at the rails. In a return-style system, the fuel should pass through the rails and back into the tank. I personally like feeding both rails in parallel. It keeps the pressure across all the injectors more consistent.
 
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tannerc91gt

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#5
  • Apr 10, 2014
  • #5
Those are the kind of answers I was looking for. Curious why the reg needs to be on the return side, especially considering the stock configuration?
I agree that parallel is the better way, and it seems like @90lxcoupe 's setup is probably the easiest way. Any real need to go -8? I assumed -6 would flow plenty for 500wheel but if there's no downside overbuilding isn't a bad thing.

Thanks guys, obviously I'm still learning some things
 

90lxcoupe

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#6
  • Apr 10, 2014
  • #6
-8 will support a ton of power and with the minimal cost difference between that and -6 lines and fittings, it doesn't make much sense to risk doing it twice. The fuel pressure regulator can be before the rail but then you can have inconsistent pressures. When it is after the rail it pressurizes the rails first and holds the pressure there. The roadkill guys put the regulator first when they did the LS swap on the crusher camaro and it got the car running but when they got on the road it burned up the brand new fuel pump.
 

stangboy

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#7
  • Apr 10, 2014
  • #7
Can somebody chime in with a definate way to route a fuel system. I just bought one but it didn't come with instructions.

This is the system I bought. Everything is pre-measured and fittings already installed on the lines. It seems to be a very nice quality system but I've never installed a fuel system before.


 

84Ttop

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#8
  • Apr 11, 2014
  • #8
 
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84Ttop

They make new pistons every day, so why worry?
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#9
  • Apr 11, 2014
  • #9
Use the pre and post filters for the pump obviously. Y block to feed both rails. Both rails to the regulator. Regulator back to the tank. Do not return the regulator to the sump portion of your tank where it feeds fuel to the pump. This is basically how my fuel system is run and I have zero issues with it.
 

RacEoHolic330

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#10
  • Apr 11, 2014
  • #10
@stangboy, if you bought a pre-fabricated kit, you should call them and ask for instructions. You'll need to route everything exactly the way the kit calls for or else nothing will fit.
 
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Grabbin' Asphalt

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#11
  • Apr 11, 2014
  • #11
I thought stock routing of the fpr is before the rails, is this not good for high hp motors???
 

RacEoHolic330

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#12
  • Apr 11, 2014
  • #12
Look closely at the stock rail configuration. The regulator is on the return side of the rails.
 
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Grabbin' Asphalt

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#13
  • Apr 11, 2014
  • #13
RacEoHolic330 said:
Look closely at the stock rail configuration. The regulator is on the return side of the rails.
Click to expand...

Oh d@mn I always thought it was before
 

stangboy

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#14
  • Apr 11, 2014
  • #14
Ok so here is the what I interpreted from the email they sent me telling me how everything is supposed to go.


Is this not a good way to run it?
 
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