So MCJK your saying no need to remove Air Flow Valve as ECU will pick up via O2 sensor that EGR valve hasnt opened, if thats the case i'd expect the 'Check Engine ' Light to come on? Wouldnt do any harm removing the Airflow Valve as i know others have done it.
Do you know the Max Exhaust temp at Turbine for the 2.8lt VM Motor?
Im looking at a Cummins spec chart now and states 430Deg C for Turbine out temp & 592Deg C at Manifold but doesnt list a Max Temp. I do know of another that listed 650Deg C Max temp.
Do you know? Are you a Motor Mech?