Also... wanted to comment on something from the same first article...
Quote:
|
Don't rely on the S-AFC to do all of the work, you really do need to use a rising rate fuel pressure regulator [like the Vortech S-FMU]. Since the PCM calculates how much fuel to inject based on several sensors, not just the MAP sensor, you need to adjust fuel flow externally [with fuel pressure]. If you keep your fuel pressure static and use the S-AFC to make all fuel adjustments from idle to full boost, the car will bog when you quickly hit the gas. It injects too much fuel and you won't go anywhere.
|
Don't forget that the GM engines that didn't come with boost from the factory only have 1-bar MAP sensors and lack fuel maps for boost. Therefore, you cannot have a static fuel pressure, you need an FMU to up the fuel pressure in proportion to boost pressure.
Also... some GM engines (like the Quad 4/Twin Cam) are speed density, only a MAP sensor, no MAF (aka "extra sensors") - so in that case the PCM
does calculate the amount of fuel to be injected solely on the MAP (and S-AFC piggyback output) reading.