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Help with LS7 Fuel System. Returnless or Return line?

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Old Dec 6, 2011 | 12:26 AM
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Default Help with LS7 Fuel System. Returnless or Return line?

I am installing an LS7 in my Pontiac and need some help to configure the fuel system. I have the factory LS7 intake, fuel rails, and 42lb LS7 injectors. I would like to retain the factory fuel rails. I have a Racetronix Walbro 255 pump already installed in the tank from my previous set up (EFI Pontiac 455) The help I need is can I run the Walbro pump with the factory regulator as a returnless system, or do I need to change out the pump. I plan to run a factory E38 computer from Speartech if that makes any difference. Depending on the answer, there is question #2 below.

Question two is, can I run the Aeromotive regulator with the factory fuel rails as a return system. It seems that the rails would need to be modified in order to make a return line. I prefer not to run any aftermarket fuel rails on this motor. Power level should be about 620 flywheel HP. Thanks.
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Old Dec 6, 2011 | 01:34 AM
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Originally Posted by Later-A-body
I am installing an LS7 in my Pontiac and need some help to configure the fuel system. I have the factory LS7 intake, fuel rails, and 42lb LS7 injectors. I would like to retain the factory fuel rails. I have a Racetronix Walbro 255 pump already installed in the tank from my previous set up (EFI Pontiac 455) The help I need is can I run the Walbro pump with the factory regulator as a returnless system, or do I need to change out the pump. I plan to run a factory E38 computer from Speartech if that makes any difference. Depending on the answer, there is question #2 below.

Question two is, can I run the Aeromotive regulator with the factory fuel rails as a return system. It seems that the rails would need to be modified in order to make a return line. I prefer not to run any aftermarket fuel rails on this motor. Power level should be about 620 flywheel HP. Thanks.
at that power level it would be easier to just run a returnless setup... run a feed and return out of the tank, to a 99-02 Corvette fuel filter which has a the regulater in it...then one main feed line up the engine bay and connect to the factory rail... the walbro 255 should feed the motor, run the main power for the fuel off of the alternator to give it a little boost in voltage
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Old Dec 7, 2011 | 01:47 AM
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That sounds easy. Thanks.
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