The short side radius of the early head is just awful. My money stays on the later head.

We have simply got to get that engineering paper translated into English!

All M104s have 10.0 to one compression. The only exception is the C36 version which is 10.5 to one.

The C36 was taken out another 60 thou over the later M104 so I would think the later M104 is still beefy enough for boost.

Somewhere around here is a thread where a guy tried to put a 3.5 diesel crank in an early block only to find that the rods hit the bottom of the bores. He found that everything fit the later block easily. (This diesel crank, along with the overbore, is of course how the C36 was created.) The 3.6 held up just fine with that later block. These are also things to consider when weighing the early vs. late blocks.
Regards, Eric

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89 300E "Benzer1" 15.924 Uncorrected
93 400E "Benzer3" 14.200 U.C.
95 E420 "Benzer4"
92 300E "Benzer5" 16.299 U.C. Future turbo CNG
87 300D "Benzer7"
87 300D "Benzer8"
87 300D "Benzer9"
87 300D/70 AMC Javelin "Sidewinder-Benzer"
87 300TD "Benzer11"
06 E320 CDI "Benzer12"
05 E320 CDI "Benzer12A"
71 AMC Javelin AMX 401 "Sidewinder"
74 AMC Hornet 401 "C.K.10" 13.63 U.C.
74 Bricklin SV1 "Presto" AMC 360 pwrd.