Variable Geometry turbochargers - been around for a few of years now - when i worked for Holset Engineering in huddersfield (they make turbochargers and turbochargers only ) i was involved with the construction of the VG assembly line (was a lectrical engineer there for 2 years) and it was some mean feat - them VG units went thru years and years of design and testing - used to love watching the test booths - they tested turbocharges to destruction on self contained units in sealed booths and also had engine test beds with dyno's on each bed - they were fantastic - 40% overfueling on an 14 litre cummins straight 6 - was pushing out over 700 horse power at 2600rpm . was asked to watch a test bed with a DAF engine on - tested that to destruction - snapped the crank in half and sent bits of engine all over that was fantastic