Hi all. I`m thinking to upgrade my a8 d3 3.0 tdi to a 4.2 tdi from 2011. This one i left it stock because of gearbox limitations. I would like to know the limits of 4.2 tdi engine and especially gearbox torque limit, i`ve seen 1100 nm on these. Would like to get a bolt on turbo upgrade if possible, or maybe turbos from 2014 model, 380hp ones can be upgraded? Would like to get around 500hp, i`m open to any sugesstions or possibilities and informations that can help me in taking decisions. Thanks.