Passat Estate 2.5 v6 tdi

Hello everybody I'm new to this forum and I would like some advice. I am currently looking to buy a Passat Estate 2.5 V6 TDI and I have noticed that some 2002 cars the sellers claim that the BHP figures as standard are anything between 163 - 170 BHP I was always led to believe that the 2.5 V6 was a 150 BHP engine can anybody help me on this as I am looking to buy a 2002 model if the BHP figures are different how can I tell the difference between a 150 and 163 BHP. Any information on this would be greatly appreciated. Is there anything else I need to look for when buying this model I'm just afraid somebody will sell me a 150 BHP claiming it to be a 163 BHP.