I'm just spewing the facts from mercedes, yet they tune the m112 power output to 230hp not the 215hp as in the crossfire.
but from that graph you do see tq starts dropping quickly at 5200rpm. it also looks like power in the graph is curving downwards at 6000 rpm, no reason in producing anymore power above 5200 anyways, since this is a rigid 90 degree block, anything over 6000rpm is getting to be a bit too shaky with vibrations