930/02 vs 930/04 Case Differences?
 

Bottom line question is what would it take to put a 2.7 crank and IMS in a 930/04 case?

Yes I researched that here! Sorry if old material.

Main bearings... crankcase bore is different.

Flywheel end of the crank…
Bruce

Right - the SC era cranks have a larger flywheel end, taking a wider ID/OD bearing in a case cast wider for the bearing. Porsche did this so it could use a 9 bolt flywheel attachment and needed the larger diameter to fit the extra holes.

To fit the earlier crank you'd have to machine some kind of insert to restore the ID for the 2.7 bearings, and figure out how to keep it in place. Sounds doable, but gee whiz, why? Doesn't sound cost effective unless you are a machinist and like the challenge.

This assumes you don't have the rather rare early 930 case for the ~1976 Euro Carrera 3.0 or the very first 930 Turbo 3.0. Those are desirable for guys making short stroke 2.8s or other cylinder diameters with the 66mm crank.