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Old 05-31-2012, 07:13 PM   #4
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You are correct , its the fuel pump not the Injectors

Idealy you want 1psi fuel psi fro each psi of boost with base fuel at 41psi , so 10psi boost you would want 51psi fuel , this is hard to do with the tuning software we have to use and the returnless fuel system , so what happens is as you go up in boost the injectors do x amount of dutycycle as the fuel psi falls off the dutycycle goes up to make up for the loss/lack of fuel psi to maintain A/F this is why it is best to always run larger injectors then needed because you burn up a lot of injector dutycycle just from not having enough fuel psi

With a return system you put a Vac line on the fuel psi regulator so every psi of boost adds 1 psi of fuel psi , makes life easier

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