Jim is right the early Euro was a different bore/stroke than the US version, but that is when we had the 733 (3.2 Green Engine). The later Euro 3.5 has the same b/s as the US 735. The differences as Jens said was that the US car was the Green version with 8.0:1 compression and 182 hp/136 kW and 213 lbft/290 Nm, O2sensor and catalytic converter. The later Euro 3.5 had the same hp as the early 3.5, 218 /160 kW and 228 lbft/310 Nm, and 10:1 compression.