Hey guys, ive been having some pretty gnarly boost creep on my mostly stock Evo 9 RS. For the couple months ive had it any time i go WOT in 3rd-5th.

Mods list -
New Stock 9 Turbo without a Internal waste-gate and flapper delete.
MAP External waste-gate O2 housing
Turbo-smart comp-gate 40
GS Manual Boost Controller currently set to 22 PSI (but creeps up to 28 and more im sure if i let it)
HKS BOV (trust me im getting rid of this)

Ive checked everywhere and have done boost leak checks and everything seems to be in order, i even preloaded my wastegate again and still no dice. Any suggestions would be welcomed!

 

Porting the wastegate holes on my BBK full did the trick. Dropped the creep from 27psi to 20psi (FP 18psi WG on WG pressure). I'm not sure if this will help as you're on a external gate.