I have a hrc stage two kit with a built bottom end. i'm only boostin 8 psi. but when i hit 4000 rpm it studders and hesitates. sometime when i hit boost the car feels like it getting no boost but is still reading 8 psi. I also have a hks bov i want to hook up? thanks for the help.

Do you have a missing link

I used to have that problem. With me it was a fuel issue. My stock injectors could not really handle 8psi. I went over to the 30ibs and now pushing 12psi daily and 15psi occasionallly and it goes strong. I beleive that some people's engines are just different from each other, they're not exactly a like.