On my safc i cant get the readings to come out right and I have it hooked up correctly. i have the pressure at 7 in 7 out. on the reading for the airflow it will only go up to 80 percent. on the pressure readings it is around -750 at idle. i know the airflow doesnt really matter that much, just as long as itisnt at 0 and kill the engine which it did one time. what is the pressure supposed to be at idle?

Stock idle is 18-20" of vaccum which turns out to 457-508mm/hg on the AFC. If you're reading 750mm/hg at idle, then something is wrong with the car selection or something else in the setup.