Thanks for the read, there is alot of information in there. I appreciate you guys thoughts on the safety aspect of this idea. This is just a project car for track use and will never see the road, but even if it did the state I live in pretty much anything goes when it comes to cars lol. I actually work on cars for a living and you would be amazed at the kind of stuff people get away with here we have no inspections of any kind. most of my experience is diagnosing and repairing automobiles.. But don't worry ensuring safety in the event of failure is #1 in my mind. I'm not a beginner in electronics or programming but I am a beginner with arduino...... and I haven't coded since high school lol mostly java and C++ but i understand code and pick it up quick.
I am also using the factory harness for this project to keep it as simple as possible so everything will be wired as factory and the sensors in question are simple potientiometers on a 5v reference circuit for the inputs to arduino. EMI shouldn't be an issue as this stuff lives far away from any major EMI source. As far as voltage surge and fluctuations I am not sure how sensitive the arduino itself is to that. But if I could make the circuit and code and install it to test I can work out any possible issues during the testing phase.
Basically trying to make something similar to a pedal commander which does a similar function of taking in the signals from the pedal sensors and altering the output signals to the ECU to change throttle response curves to the drivers liking. Just instead of just basically amplifying the input voltage for the output like a pedal commander i need to take in a voltage and output a different voltage over a range of 0-5v on 2 channels.
The car will have an E-stop that kills ignition and fuel as well as cut the battery all together. Will also have an inertia switch that will kill fuel in the event of an crash. I plan on installing the signal converter on a breadboard in the car at first during testing so I can introduce all possible failure scenarios easily and make sure the ECU responds as it should before it ever moves.
The reason the pedal has 2 opposing sensors is for this reason. If 1 of the 2 sensors or both fail, output the wrong voltage, don't correlate with each other, etc. the ecu will throw a code and should get thrown into a limp mode state to disable the throttle and only allow the engine to idle which is a built in safety feature in the code of the ecu. I plan on doing extensive testing to make sure that any possible failure to the part I make will throw it into limp mode. Once I go through function and safety testing on a breadboard then i'll 3d print an enclosure and make the final install.
But trust me I have not overlooked safety lol. I understand and appreciate the thought experiment, the part I want to try and use is the original part to the car, but not the original part to the engine swap ECU. and its not that the part that would just work properly is a bit bulky kind of thing, its more of a it just won't fit at all kind of thing lol.
Even though the only person that will be in danger is me crashing into a wall on track I still don't want a runaway throttle for any reason and will make sure its impossible for the arduino to cause that. I would never carelessly put something on a car that could kill me or someone else, i've driven enough customer cars that tried to kill me I don't plan on adding to that madness lol.
I was thinking using 2 arduino nano would be the best option. 1 for each pedal sensor. Each would have its own separate code and just a single input and output with a DAC on the output. please correct me if i'm wrong or there is a better way, I wouldn't mind a bit of input on the hardware side
Sorry for the rant, but I am a very safety oriented person lol if I didn't know that there are already safety features in the main ECU for this then I wouldn't even attempt this.