Originally Posted by
RomansDesigns
100% duty cycle means the injectors are on 100% of the available time. 100+% = STATIC, the injectors are wide open. At this point you are hoping the FMU is giving enough pressure that you aren't leaning out, but the ecm has lost all control. I had this on a 5.3 with a Vortech and FMU. We took the FMU off, istalled a set of SVO 42's and I was able to get the WOT AFR's to about 12.2 to 1 and not hit over 80% duty cycle. (We had to install a bigger fuel pump too)
Mark