Those Corsa's are light as you know, can you strip the cr@p outta your Golf for the drag? Rear bench, spare wheel etc.
Standard VXR "NurBUR--big-track-tricky-corners-BER_RING": Power/torque: 202bhp @ 5,750rpm/207lb ft @ 2,200-5,550rpm + or minus less weight... as a starter.