I agree. Some of the posts should be moved as they are more safety related than pre-comp related.
The problem with the sensor being wetted is moot, it is heated to 220C above ambient to prevent this already. The amount of current needed to maintain that temperature determines the mass-flow through the system.
Even if it were wetted, so too would the rest of your induction be. Therefore the WI effect would taper off slowly. Which is exactly what was seen in that dissertation I posted from Linkoping on WI.
Since these are resistors, and very accurate ones at that, all you really need to do is this:
1. Have the sensors active at all times, but passive.
2. Have a boost pressure solenoid that activates the safety circuit just as your WI comes (at a fixed boost pressure) on and deactivates as it goes off.
3. Have the first PTC resistor (RH) heated to 220C above ambient. (Ambient temp is measured by a third special PTC resistor (RC)) The amount of voltage required to keep that sensor at that temperature differential will depend on the mass flow of the air across the (RH) sensor.
4. Have a third resistor post-WI "wet" (RH) which is heated to 220C above the temp of the special resistor (RC), and if the value is equal, or near to, your "dry" PTC (RH) resistor the power to your boost solenoid should be cut (thus limiting you to base boost, which should be knock free) ...
5. If the voltage required to maintain the second "wet" (RH) PTC resistor increases significantly while the safety system is active (step 2), which means the power required to keep it hot has dropped, power should be cut to the boost solenoid. The level of drop which causes this should be adjustable becuase the WI may not produce a 100% constant cooling effect.
Make sense? Should be relatively simple to setup with the right tools and electronics knowledge. The parts could be scavengened from any GM Mass AirFlow sensor. (Each contains two PTC (RH) resistors and another PTC (RC) resistor.) Pricing is in the $200 though.
If your car is injecting pre-turbo and already has a MAF sensor, you'd just need a second MAF sensor. The value of the second one should just be significantly higher.
Adrian~
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