Hmmm, I believe if you are overboosting and you are not changing the wastegate spring....Then the Boost Controller won't help your overboost. Alll the BC does it control when the wastagate is exposed to the signal boost reference so if it has a 10psi wastegate and a 15psi boost goal, the BC will not allow the boost signal reference to reach the wastegate until you reach 15psi. But the lowest boost pressure it can achieve is to allow the wastegate to see the signal the whole time....the same as having no boost controller at all