I have plenty of books as well, but all the info for these posts came from the Porsche 911 Red Book, by Patrick Paternie. Sorry to disagree, Banzai, but MFI is very tunable, if you know how. It makes the same power or better than carbs and has OMG instantaneous throttle response. The best I've ever experienced, bar none. Think about it, with carbs the venturi and fuel discharge are in the way of the air, not so on MFI. And it's sequential to valve opening, ahead of it's time really. The 2.7 RS and 2.8 short stroke RSR both had MFI.
People remove MFI and put carbs in because it's easier, sometimes cheaper($$re-bush throttle bodies & rebuild injection pumps$$), and they simply don't understand MFI.
CIS requires too many compromises with respect to heads/cam/valves for a racecar. I was simply referring to factory issue regular 911s.
My favorite engine is a twin plug MFI high compression 2.7 with S cams. Easy 250 horses or more. As far as I'm concerned, the last 911 was made in 1973. Long hoods RULE!
So let me get this straight: you're concerned about originality/history when you've got a hot-rodded flat six in a replica of a car that never had a six? Ironic.