Known facts about the Grand Prix GXP 5.3L Displacement on Demand engine as I have figured them out today (12.28.04)
New picture directly from the GM software manuals.
Check out the starter. It is circled in red and green. Notice the direction. It is pointing toward the front of the engine. I have concluded it bolts to the back of the block somehow, but the transmission will have to have a cutout for the starter to fit in seems like.
Why is the AC compressor missing from this picture? The belt is pulled out like there should be a pulley there, and that is where the compressor is on my GM concept built project.
Check out that exhaust crossover. If all this fits the LS1 and LS6 engines, you will still need an adapter plate to mate a GETRAG, or a 4T65eHD transmission to those engines.
Rear of the engine shot with the new knock sensor even showing, and the DOD lifter valley cover bolts.
Now I can almost be 98% sure the bolt pattern of the engine is not the small Metric pattern.