Modifications made -
Kooks mid-length 1-3/4" Headers;
Kooks Off-Road H pipe (No Cats), Front & Rear O2 Sensors installed on each Bank;
JLT Big Air 123mm CAI ;
Larger Throttle Body FordRacingPerfParts Twin 65mm Cobra Jet TB
Triple pass, Dual Fan Heat Exchanger;
170 Deg Thermostat
+10% HarmBal Pulley
(Factory Fuel Injectors)
I notice when doing WOT pulls the initial fuel injection duty cycle spikes up to drive the WideBand O2 Lambda to the Commanded Lambda (0.76). The duty cycle spike is less than 100% when in 3rd gear (or also 4th) but when I am in 2nd gear (say 4,600rpm at 60mph) with either TracControl On or Off (both difficult to keep from spinning tires) the InjDutyCycle spikes up above 100% and DriverDemand Limit Source says Insufficient Fuel Flow (for instance 15:56 time point).
Even though this is for a brief moment and perhaps tire spinning, I am wondering if I need to be concerned and if there is something in the tune I should change or if fuel injector size needs to be increased (these are stock injectors -57 lb/hr I believe). I was told the stock fuel injectors should support the mods I have done.
Hook up a actual fuel pressure gauge to the car and see if your losing pressure on the hit, could be your low on gas and it's moving to the back of the tank away from the pump pick up. It looks like you have enough pump and injectors since your IDC come down once you are in the higher RPM range, so could just be the fuel moving back. You can test this easily by filling the tank and trying again, but would still be a good idea to run a fuel pressure gauge to see what pressure it's running.
You do not have a MAP sensor and MAP is being calculated from MAF, which is looking fairly accurate to me. You are hitting MAP max delta above baro and MAP max vs airmass under speed density. I would just move them up out of the way if you are confident you have enough pump and injector for your expected airflow, or at least high enough to make sure the fuel pump can hit its max duty cycle and not rely on/ over work the injectors.
An accurate MAF and injector/ fuel system data usually leads to a accurate calculated MAP. It can't increase rail pressure through pump DC accurately if calculated MAP is being limited. It will close the throttle to limit airflow and maintain the MAP limits. How much more boost than ~15-16PSI are you expecting?
I did try reducing the Power Enrichment Rate from 1.0 Lambda/Sec back to stock 0.7 Lambda/sec and did not see any change or improvement in reducing the Injector Duty Cycle (see attached files). I also made sure the fuel tank was full when I did the latest WOT 2nd gear pull. I had logged additional fuel flow rate, pump DC and rail pressure before and looked OK but will check again.
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