I was at a car show yesterday and they had a Type S there. I think Greddy was right about the room in the engine bay. There is at least twice as much room between the engine and the firewall it seems. It is the same with the new SI, plenty of room there too. Though I can't figure out how either could have a cai installed.
It seemed possible for the RSX but it would take a lot of work. With the SI though when you look in there it is just solid from all the stuff in the way. I couldn't even find a spot where I could see any part of the floor or anything. It was whack.