997 has a shorter stroke (allows them to go 3.6/3.8 vs the 996 3.4/3.6 with the same bore size); jake is most likely moving the 997 crank into the 996 (or a custom version of the same to fit the 996 bearing surfaces, etc.) and using a 3.4 bore diameter - that'll get you 3.6 (with the option to go to 3.8 without thinning the cyl walls too much). this is why 997.1 had piston slap issues - shorter stroke meant con rods at a higher angle to the piston and the alusil or whatever it was that Porsche used would wear; the stonger lne nikasil liner addresses that (Porsche moved to a better liner with the 997.2).
expensive way to go - need a whole new bottom end; cheaper to just bore out to 3.6 and be done with it, but you lose the benefits of reduced rotating mass, faster revving, etc.
edit to add - my post should read more as a question than a statement - ie, thinking out loud - as I try to appreciate the work being done here!
Last edited by The Radium King; 06-09-2015 at 11:39 AM.
Reason: clarity!
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