Discussion and questions related to the course Reflashing
The car is bone stock with the exception of the wet nitrous kit. I have a dedicated fuel enrichment system that I will be using with C16, while running pump gas (91 octane) in the factory tank. I am also running a progressive controller to ease the nitrous in to prevent wheel spin and excessive shock to engine components.
I believe that the newer Fords will always run in closed loop correct? If this is the case then I should be able to first ensure that the car is hitting the fuel target before introducing the nitrous, and then tune the nitrous jetting/fuel pressure based on how much fuel is being added/removed in the short term fuel trims? Just curious to see if this is how you would do it?
Part 2. Will the increased torque produced by the addition of nitrous oxide require changes to the torque tables since it will be added completely independently?
Hi Matthew, yes, the late model fords use wideband O2 sensors and run continuous closed loop control. Since the nitrous is outside of the factory ECUs control I don't see the need to modify the torque tables - Basically the factory ECU would not know more oxygen is being introduced to the engine. My concern however is how you intend to retard the timing when the nitrous is active. This is one of those areas where often it's a little tricky to manage nitrous with a factory ECU.
I will have to set my max allowable advance equal to the borderline table for the nitrous tune as I have not found a piece of hardware capable of retarding the ignition timing only when then system is active. The intention of running race has in the fuel cell is to mitigate the need to pull as much timing, which will keep the car from being a sluggish pig NA. I may also only set the ignition retard just before the 5K RPM mark, and set the nitrous window to start spraying at 5K RPM. This will maintain the drivability around town.
Any specific recommendations or known changes people generally miss when tuning to not allow the ECU to add timing on it’s own would be greatly appreciated. Using HP Tuners.
Your plan sounds pretty sound. A colleague of mine has done a couple of nitrous installs on GM vehicles and used a relay to essentially disconnect the IAT sensor when the nitrous is active. This has the IAT revert to a fault value and he then uses the ignition modifier table to tweak the timing under just this condition (fuelling also obviously needs some tweaking). I can't say if this would be achievable on the Ford PCM but worth a thought.
If your base timing is on point with the nitrous active you should be ok as the knock control system is still there to protect you and essentially you shouldn't have the timing advance by itself and cause knock.