blue is old s trim and red is new t trim

 

Looks like slip. The leaked areas are where it's starting to grab then fails again. There is a slight chance it could be a weird boost leak but usually those just drop straight off and stay down.

Also, if a new standard bpv doesn't fix it then putting a n upgraded one on it won't do squat since the bpv is closed during wot. Don't be duped into buying something you don't need. Look elsewhere for the problem.

 

Dead on about the slip I went a bought a little smaller belt then what they had one there's no more issues it hits 12psi no problem now just gotta take it back to the tuner

 

glad to hear it was a simple fix!


make sure you get some miles on the belt and then re-adjust it before going back to the turner so it won't stretch and then start slipping during your dyno tune again.

 

I would check the hose coupler on the volute. Since it is drafted in that area I have seen clamps be tight but leak through the drafted area if the clamp isn't close enough to the bead.

 

How much did you gain?