It's going to cost a fair whack to go from stock to stage 3 with a tte420.
Turbo - around £1800-1900 for a new unit
High pressure fuel pump - £500
Low pressure fuel pump - £200
Turbo back exhaust -£700-1000
Intercooler upgrade - £250-600
Induction kit - £300
Uprated clutch/flywheel £750-800
Fuel pressure valve £150-200
Remap £550
Optional/recommend extras
Brakes
Engine mounts
Water meth injection
Runner flap delete
Larger boost pipes
Pcv delete
May have missed some items but that's the gist of it really
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