Interesting data

So I have this chip that is supposed to record data through the OBDII connection on my DTS. Well I've had it recording throttle position, speed, Manifold pressure, etc etc. One oddity that I've noticed is that at full throttle, the manifold pressure never gets past 10.4 psi. My vette on the other hand comes closer to 14.5, which is almost atmospheric. If the caddy is only seeing 10.4 psi in the manifold, that should mean that there is a SERIOUS restriction somewhere upstream. That would be either the filter/intake assembly, the MAF sensor, or the throttle body. If we could eliminate this restriction, we should be able to see an significant improvement in power. I'm going to hook my laptop up to the car and see if I can come up with a more detailed set of data. Any thoughts would be appreciated.

Scott