***Ram jet 350 problem ***

So your RamJet does not have an O2 sensor? Your suppose to have it ... if you do not have it you cannot idle nor will it tune correctly.

 

02 for idle? Non-heated sensors do not function well at idle.
I don't know if early MEFI units had input for 02 sensors. My Black Scorpion definitely does not have an O2 sensor.
I have a wide band on my Suburban. It's used for tuning.

 

In closed loop mode the O2 is used from idle to 3000 RPM and heated option on the O2 is only to get the O2 up to temperature sooner once the O2 sensor reaches temperature it is used all the time and the heater voltage is removed by the ECU because the exhaust will maintain temp.

If you do not have an O2 then you are a ALPHA-N EFI system which uses the position of the throttle and RPM to know the settings ... the Ramjet is more intelligent then that:

http://www.hotrod.com/articles/ccrp-0802-electronic-fuel-injection-system/

 

No intention of starting a pizzing match but you obviously didn't work on cars during the 1980's. They would fall back into open loop at idle because the exhaust didn't carry enough heat to keep the sensor active. The o2 is really only there to keep the catalytic converter happy anyway. Sure they help with tuning. Who want to carry their gas analyzer in their car? There are plenty of examples of EFI running without an active o2 and still idle and run fine.

From the little reading I've done, only the latest Ramjet controller, the MEFI-4 has o2 input.