...I can't believe I'm doing this
I think you guys have what Gary was saying a bit muddled up. By my recollection, he wasn't counting the amount of air in the 'intake chamber', 'combustion chamber' and the 'exhaust chamber' as Jez put it, but he was counting the combustion chamber 3 times as that is how long it took the rotor to finish a full cycle and come back to its original state. therefore, it doesn't matter if the intake chamber is 9 billion litres, that would be like counting the plenum on a skyline...
This is why 20 odd pages were about what a 'cycle' consists of, and there was no unanimous decision.
PLEASE don't start arguing again, I just thought that had to be cleared up!