A set of second hand 17” wheels with 4 new balloon tyres would be a lot cheaper than a new set of decent gas pressurised dampers and Golf TDI springs plus associated fitting costs and alignment etc.
Seriously, if going to all that trouble to fit wobbly suspension to a sports hatch I think I’d rather just chop the car in for something French and be done with it.
Firstly the springs would have to be correctly load rated for the weight and output of the engine/gearbox combo and then declared as a modification to the vehicle. Then you’d have to make sure the dampers matched the springs and other ancillaries likewise, plus you’d have to fully set up the suspension for the changed ride height which will likely affect much of the geometry settings...
In the past I’ve found on previous generation Golfs that just adding uprated gas dampers from the likes of Bilstein or Koni (not their very hardcore sports dampers) but retaining the standard factory springs did improve ride and handling, with the higher quality dampers controlling the spring oscillations better. But on the MQB cars that balance is already pretty good even on 19” wheels.
I think you bought the wrong car for you.
