I have thought of something like this as well. I was not planning on using a separate pressure sensor, but instead a feed off of the stock map sensor. The output ranges of the map sensor can be converted to any range you want via an amp circuit. So when the map sees atmospheric, it puts out 4.6 volts I think. That can be amplified to 5 volts and feed into the TPS signal to the ecu. The variable resistor on the throttle body simply changes a voltage that the ecu reads. You just need to tap into that line and feed the ecu the correct voltage and keep that voltage from going to the sensor. Use a diode so that the voltage can only flow one way, but only at 0 psi boost and above.

I have only thought about it.... I have not actually looked into the physical aspect of it. I know what needs to be done though. If I said anything wrong up there dont kill me.

If nobody else needs something like this, I will be developing something anyways since my car is undergoing boost transformation.

-Jared
96 GS
Melbourne, FL