997.1 vs 997.2 — engine architecture is the sub-generation decision

The 997.1 (2005-2008) uses the M97 engine: 3.6L base, 3.8L S, with the IMS bearing (sealed/non-serviceable from 2006) and a known 3.8L bore-scoring risk that experts believe is driven by cold-weather DRIVING HABITS not geography. The 997.2 (2009-2012) brings the all-new 9A1 DFI engine — described by experienced owners as 'bulletproof without cam or coolant pipe problems like Mezger', with the trade-off that it doesn't carry the Mezger mystique ('wet-sump consumer-grade engine' per one expert). …