i am having a problem.
While tuning, found out that the boost dropps in high rpm around 7500 rpm.
Was running about 18~19 4400 psi then drops to 10psi in 7500 rpm.
any idea why?? If anyone want to see the datalogs I could send it...it just doesnt want to hold the boost at all...

Turbo del sol d16z6
.48 trim turbo (did not want to notch block)
Hondata s300
Bottom fully built (except CCS)
manual boost controller (boomba)
ebay 38mm wastegate
7 pound spring

 

Ebay wastegate with spring that can't hold boost pressure past 2x the spring is a common issue