4.2 TDi - difference between 350PS & 385PS?

[GlynH]

Hi there, a quick question hopefully!

Just what is the difference between the 2010 A8 4.2TDi putting out 350PS and the 2013 A8 4.2TDi that puts out 385PS?

Apart from 35PS of course!

Is it simply a different map using the same components or are there any physical changes such as different/bigger turbos, cams, heads etc?

Curious to know what changes Audi have made to the engine to achieve the extra 35PS...

Thanks & kind regards,
-=Glyn=-