He's not reading it right. The graph is ancient...he would freak out reading the new one.
The Map KPA reading is in absolute pressure. You have to remove the atmosphere, here at low altitude, remove 100 KPA...
So we are running 64 KPA of boost (8 psi) on the stock 3.8 pulley.
Now my MAP sensor is maxed out at 200KPA (14.5 psi of boost) but I'm running more. Around 18 psi of boost currently with the 2.6 pulley.
I peak at 37 Lbs/min which means I'm over 350HP probably closer to 370HP (at the crank)