I may have a similar problem. My car is a 2004 BA XR6T Falcon Sedan Manual 5spd. I am running 96 octane fuel. I live in regional Queensland which makes finding a specialist a bit more difficult. Around town, I can boost hard (up to 80kph or so) in 1st and second gear and the car performs flawlessly. If I'm out on the open road and then foot to the floor boost for what seems to be a little over 3 seconds (lets say 3rd gear passing a road train or something) it will suddenly loose all power and the engine will shudder. I naturally button right off immediately but it seems the engine is still shuddering and has no power. If I then pump the accelerator pedal 1/4 of the way down a few times the shudder seems to go away and it's back to normal. This does not appear to be a traction control issue as it does it with the traction control turned off and if t/c is on, the light does not indicate a loss of traction. I am trying to decide on the best solution for repairs and am interested in anyone's experience or knowledge in this area. Any help is greatly appreciated.