Now my custom turbo back exhaust has been fitted,(by Exhausts UK,Sheffield)the car's suffering with boost problems. Steve Jr at Statller reckons it's the exhaust that's causing the problem,and recommended putting the old exhaust back on,and then data logging,but obviously that's gonna cost...and then a replacement(maybe my custom one,modified?)or Milltek will have to be fitted again...more money... Although it has a 200 cell sports cat,the complete system is flowing too well,so not creating enough back pressure,causing the turbo overboost,so i'm losing torque. What should i do? Spend more at Exhausts UK,fitting another cat or something to restrict the flow? Spend even more and go full Milltek? I've no idea what i should do next! I've even considered just having the Milltek downpipe and sports cat,but the combination still might not flow correctly with the rest of the system. Its currently a 3" downpipe,200 cell sports cat,2.5" pipe,mid silencer,2.5" pipe,cobra rear box. I'm running a GIAC hammer map and Forge CAI,both worked seemlessly before the exhaust went on.