Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum - View Single Post - FI Duratec fuel requirements
View Single Post
Old 05-31-2012, 08:30 PM   #5
Focus Addict
sutyak's Avatar
Join Date: Sep 2004
Fan#: 12724
Location: Fairmont, WV
What I Drive: Turbo 04 DSG Mach 1

Posts: 1,492
Points 15,704, Level 80
Points: 15,704, Level: 80 Points: 15,704, Level: 80 Points: 15,704, Level: 80
Level Up 71% Completed
Level up: 71% Level up: 71% Level up: 71%
Forum Activity 0%
Activity: 0% Activity: 0% Activity: 0%
FF Reputation: 62 sutyak Excellent Standing Member
Buy-Sell-Trade Rating: (16)
Originally Posted by 1turbofocus View Post
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

That does sound simpler to tune for. Know where I could find a list of parts necessary to convert to a return system?
'04 Mach 1. Built. Turbo. 667whp/631wtq
'06 Focus. Built. Turbo. WMI. (sold)
'03 Mach 1 : 12.61 @ 106.59 (sold)
sutyak is offline  
    Reply With Quote