hi peeps, just thought i'd throw this up for ppl having overboost issues with stock systems ..my problem i had.. when i converted to terb on my N/A i could never get it to stop creeping past 12psi & visciously pinging on stock 'VLT' setup with a 3'' zorst, it was doing my head in & whatever i done it yielded no result. now on the 21st i went to heathcote (drags) to see what it'll do but to no suprise it popped the head gasket & melted the sparkies. so..some ideas came to mind.. ~if it's still boosting with the flap 100% open the wastegate hole must be too small~ so off with the dump & whatya know! tiny pissi asss wastegate hole! so i got the rasp out (also known as a dremel) & opened her up..put it all back together & wala! she now sits on 6psi & doesn't move all the way to rev limit.. it pulls much harder than ever & the motor & terb run much quieter & both run in sync! hope this helps someone as it helped me, i'm sure theres a lot of ppl with the same problem.. peace!