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help with fuel system setup

  • Thread starter Thread starter Charged90LX
  • Start date Start date Oct 2, 2004
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Charged90LX

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Sep 9, 2004
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Oct 2, 2004
#1
  • Oct 2, 2004
  • #1
I got a walbro 255 fuel pump and some after market fuel rails, 36# injectors and a fmu. I was wondering what else I will need to finish my fuel system. what hoses/lines will I need? Do i need another stock fuel pressure regulator or is a fmu all I need? The return line is the small one and the feed line is the big one?
 
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Charged90LX

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#2
  • Oct 2, 2004
  • #2
so no one here has an aftermarket fuel system?
 
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Daggar

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Jul 19, 2004
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#3
  • Oct 2, 2004
  • #3
How much power are you puting out that you need 36# injectors AND and FMU? What ratio is the FMU? How much boost on what size motor? What's your compression and N/A output? Do you have a way to read your AFR once this is all hooked up?
 
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Charged90LX

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Sep 9, 2004
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#4
  • Oct 2, 2004
  • #4
Daggar said:
How much power are you puting out that you need 36# injectors AND and FMU? What ratio is the FMU? How much boost on what size motor? What's your compression and N/A output? Do you have a way to read your AFR once this is all hooked up?
Click to expand...


Its gonna be over 500hp. I dunno what the ratio of teh fmu is but its what came with the vortech kit. I am thinking about an aeromotive afpr. compression is 9.1:1 I have no way to read the afr once its hooked up.
 
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Daggar

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#5
  • Oct 2, 2004
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Ok... You have allot of unkowns there which isn't a bad thing necessarily but here's the thing. I'm betting that the FMU that came with that kit is liekly a 10:1 and did not have your 36 lb injectors in mind (meaning that it will ramp up your fuel pressure too much). The adjustable fuel pressure regulator that you're talking about can help to offset that but you won't know where to set it without kowing what the AFR is at boost, part throttle, and WOT. You must have one hell of an engine and block in that car if you plan over 500HP and if that's the case and you plan on going with Aeromotive then you should consider getting Aeromotive's complete fuel system. I don't believe that the stock plumbing will handle the volume of fuel required to support over 500HP. At any rate... you're going to have to find some way to tune it once you get it all together... either by taking to someone with a chasis dyno who can tune it properly or by having at least three things to do it yourself: A wideband AFR reader, Boost/vac guage, and fuel pressure guage. Without those things, all you'll be doing is guessing.
 
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Daggar

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#6
  • Oct 2, 2004
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Post information about your engine and all of your mods as well as your blower and how much boost you intend to run. At least that way, someone with a similar setup can help get you close.
 
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Charged90LX

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#7
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I have a post in the power adders that has my mod list.
 
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