8-9 PSI on stock pulley?

Maybe in the cold...maybe.

Most stock cars with factory exhaust pull about 5-7 psi at the shift....the restrictive part is in the manifolds/DP...6 psi is probably about right.

I'd do a pan drop and see what's going on, get a shift kit from Intense-Racing if you haven't cracked into the transmission yet...as I'd also recommend checking the cat if you haven't...could be clogged...could also be what you thought of the converter dying out on you as well...