Originally Posted by
Chip
Mike, yes my understanding as well is that basically they have got a 1.87 max scale value on the map, so above that it will just flatline the fuelling.
Ie at 2.1 bar it will have exactly the same fuelling/timing as at 1.87 bar. Which cant possibly be correct for both boost values at once of course at that extra 3psi changes the optimum values.
You can extrapolate the fueling curve above this, as I have seen the paper graph that Ahmed refers to to do this, but as I stated, you would only normally do this when you go above the maximum reading of the MAP sensor. Obviously if you're running a T4, the scaling used should reflect (as much as possible) the range of pressure the engine is going to see. I agree that it isn't a good idea to use scaling for a small turbo on a big turbo.
However, I'm just trying to put all the information out there, so that people can actually understand rather than just jumping on the band wagon.