ls1 fuel system help
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hello,
i currently have 95 lt1 donor car and im swaping a 99 ls1 into it. i was wondering what all has to be done to modify the lt1 fuel system to work w/ the returnless ls1 system. i already have a walbro intake 255 and would like to hear all my options about constructing the proper ls1 system. should i upgrade the lines, or rails, or different pump. etc.. what all needs to be done, i have stock rails, and 42lb injectors.
thanks,
Nick
i currently have 95 lt1 donor car and im swaping a 99 ls1 into it. i was wondering what all has to be done to modify the lt1 fuel system to work w/ the returnless ls1 system. i already have a walbro intake 255 and would like to hear all my options about constructing the proper ls1 system. should i upgrade the lines, or rails, or different pump. etc.. what all needs to be done, i have stock rails, and 42lb injectors.
thanks,
Nick
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Really all you should need to do is put a regulator in the rear of the car and set it at 58 psi. Don't hook up the vacuum reference. Cut the factory retun line and put the return into that.
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ok so now i purhcase a plastic tank and fuel pump etc assembly from an ls1 99-newer vehicle. how do i run braided lines to the rails? do i need a regualter..
help me please!
help me please!
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it will be cheaper to just replace your stock fuel pump with a vette fuel pump (has a built in regulator) you can get this from www.gmpartsdirect.com
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OK OK you are making this way too difficult. How much power? Just a stock motor? The steel tank will be easier to work with in the long run. You can add 97-98 Vette rails and plug in the factory LT1 lines. Or you can just add a aftermarket regulator back by the fuel filter and run a short line right back to the fuel tank for the return. There will be some odd fittings and such for this route. There are many different ways to go about this.
Nate
Nate
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no it is not for a stock engine or even near stock power levels. i want it to be able to support around 450-500 on motor and a healthy dose of n20 (150-200), right now i have an intank walbro 255 in the metal tank, but plan to swap it over to the plastic tank.
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So basically you need a fuel pump/system that can support 700hp?
Shouldnt be too hard to find a thread about the required components to handle 700hp w/ spray. You may have to do a little custom plumbing between the tank and engine. Upgrade your lines, injectors, go with dual walboro's or something similar.
Shouldnt be too hard to find a thread about the required components to handle 700hp w/ spray. You may have to do a little custom plumbing between the tank and engine. Upgrade your lines, injectors, go with dual walboro's or something similar.
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yea thats what i have done. but i'm unsure of the custom plumbing required for ls1's i'm a newbie when i comes to ls1's i have two lines running all the way up from the tank on my car... one being a return and the other supply.
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I could be totally wrong,but from what I gather you old lt1 uses a supply line from the tank to your fuel rail then to a built in reg. then a return line to the tank. On the ls1 it only uses a supply to the fuel rail. the return line comes of the fuel filter. short line back to the tank as a return. fuel filter has 2 fittings on one side (inlet) and one fitting on the other side.(outlet) you will need a inline reg. after the filter no reg. on the ls1 fuel rail.Tim
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I would at least stick with the metal tank as they take dual Walbro's easier and safer than the plastic tank. Run some -8 to billet rails out to a regulator and either -6 or the factory feed line back to the tank.
Or run one of our sumped race tanks and our complete 900hp fuel systems for a better more reliable fuel system.
Nate
Or run one of our sumped race tanks and our complete 900hp fuel systems for a better more reliable fuel system.
Nate