The first question Simon asked me was "how does the tune feel after the update" The first thing I noticed was the lack of power thru out the rev range ,,but the idle was smoother On the dyno it confirmed the reduced power...The update had altered the fuel and spark of the original PCM tune This inturn had thrown the unichip out , as the unichip was bending the newly altered PCM maps which resulted in an out off tune engine The Ford dealer I go to also have had instances where updates have caused chipped cars to not refire at all... After 1 1/2 on the dyno and a test drive listening for detonation ,Vixen's power is the same as it was before the update... The only thing that has improved because of the update was the idle quality..Much more consistent now..We put the previous idle fluctuations down to the aluminium flywheel (4.6 kg lighter than stock flywheel) during the clutch upgrade.. JB have you had your air/fuel ratio checked since the update? The Air/fuel ratio I noticed was reading lean when we done the dyno run