The most common cause for shut down is lack of fuel pressure. These suggestions are made ssuming your engine is well tuned and in good running order; has good compression and leak down test numbers. Overboosting an old, worn, tired engine is a sure way to turn it into a hand gernade.
Here is the typical order of operations I use:
1. Upgrade and overhaul the fuel system. You are probably shutting down because the pump is tired.
a. Make sure the tank is clean
b. Replace every rubber hose. Use FUEL INJECTION HOSE and FI CLAMPS
c. Replace the fuel pump. 190 lph is probably plenty.
d. Have the injectors cleaned. Mr Injector - Home
e. Replace the fuel filter
2. Swap the Mitsu for a Garrett with a 2.5 inch swing valve
a. You can run the same boost levels (13-14 psi) with better results because the Garrett moves more volume, spins slower and doesn't create as much heat as the Mitsu. It's not all about pressure.)
3. Install a free flowing 2.5 inch exhaust, you should already have a 2.5 inch down pipe. A ported exhaust manifold is a plus.
4. Install a good cap and rotor along with a GOOD set of ignition wires. New plugs too if you haven't changed those already. (RN12YC)
5. Install a Mopar Performance SBEC for better spark and fuel curves. (P4529998 auto, P4529999 manual)
6. Use a manual boost controller to dial in the boost.
7. Add air/fuel and boost gauges so you can see what is going on.