Vac leak or just pressure drop

[Bad40r7]

Well guys, im still a noob to the sr20, but am catching on quick. Bare with me a little...I have a redtop, and im assuming its a t25. I have a 3inch front mount core, with the normal legnth pipes. Before, my bov O-ring was ripped, so it was leaking boost like crazy, now that i have a new one, its better, but still not what i expected. If i am rolling in 2nd at say 25mph...and put it to the floor, it will go, pull out of vacumn, to about 2psi...and then very abruptly shoot up and the car will start pulling. Is this because im loosing so much pressure because of the front mount.

And a quick one, i have an HKS actuator...i have been adjusting it, making it longer...and havnt noticed the boost moving past about 6psi.

Thanks guys.
-Alex