I was reading in the boost forum earlier today about a solution that someone found to the low map voltage code that has been going off with e-managed installed. They put a resistor in parellel with the map sensor (connecting the 5v input with the output) to increase map signal voltage. The problem with this on a regular set-up would be that it would richen the car. Fortunately for them, they have e-manage which they can tune the car right back to the correct A/F with. I was thinking about using the set-up with a dry nitrous system. I have been 100% unable to find a map signal modifying computer in order to incorporate the stock injectors to add fuel for a dry nitrous kit. That's when it hit me, if such an adjustable computer existed, all it would be is a potentiometer (a variable resistor) and a relay. Now I am ready to trry this. Here is my idea:
The relay would be turned on by the hot wire of the nitrrous solenoid, just run it parallel to it. The circuit the wire would connect would be parallel circuit to the map sensor. Just like they did for emanage, it would connect the 5v map input to the output signal. in this circuit would simply be the relay and the potentiometer. By adjust the potentiometer to different levels of resistance, you would be able to control the map signal voltage that the computer sees and it should add more fuel by increasing the duty cycle of he injectors. When the relay is off, this would be anincomplete circuit and it would not do anything. By simply mounting the potentiometer dial inside of the car somewhere, you could adjust where exactly you A/F ratio would be while nitrous is engaged.
Am I missing something here!? The only thing I can thing of that would prevent this from working would be the limited duty cycle of the fuel injectors,But since dry kits decrease engine vacuum and raise fuel pressure while engaged, this wouldn't be that bad. You can richen it until the injectors reach 100% duty cycle. After that, you need a wet kit or bigger fuel injectors. Should you put on larger fuel injectors, you could tune down the idle in the same fashion by placing a potentiometer in series with the output signal ofthe map. This also would not work on boosted cars since we have 1-bar maps.