Welcome to the forum mate.
I have had 125 on the clock on my mk3 16v, and was doing just over 5k on the revs, so I imagine that 143 on the clocks is easily attainable, I have gps'd my speedo and found it to ber 3mph over at 85mph.
I have a magnex twin dtm on my car, and no induction kit but I would suggest going for a k&n.
Hope you enjoy the forum.
Paul