Another issue:
"Why am I only getting X psi boost in 1st gear, but I get Y psi in 3rd gear?"
Again, this is not something unusual and there is nothing wrong with your car. No, the SRT-4 does not have the world's smartest super-computer under the hood.
The answer has to do with how much the engine is being loaded down. It's the same reason why you won't see any boost when you rev the engine with the trans in neutral. When the engine is loaded it requires more fuel and air to make enough power to handle the load. Put a load on the engine, for example, pulling a trailer with a boat on it, or going up a steep hill. You mash on the accelerator to keep speed up. The engine wants more air and more fuel, exhaust flow and temp go up, boost comes on faster. The computer is not controlling the boost as much as the exhaust is. The computer will limit how
high the boost can go, but that's about it.
Find a steep hill near you and try it. Put it in 2nd or 3rd gear going up the hill and stomp on it. Now do the same thing on a flat, level street. Boost response will not be the same.