To get over 300bhp you would be looking at a GT2871r Eliminator kit or a self built GT28RS or Full GT2871 kit but to get 350bhp and not worry about the boost you will need to put in a set of rod's and may be pistons to be safe.
If you have the funds look for a face lift car these came with K03s turbo giving 180bhp stock and will remap to around 210-220bhp.
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OEM RS4 Body| RS4 front Brakes| RS4 shocks & H&R Race springs| RS4 Xenons| 18" BBS RC wheels| Scroll K04 Outlaw|RaceTec FMIC| Southbend StageIII clutch| Autobahn88 Silicon hoses| Baileys DV| Waiting to be fitted: TT MAF| 380 injectors| RS4 Rear brakes & a Remap
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