Unless you are prepared to build some industrial strength equipment of your own design and then move everyone in the neighborhood away while you experiment with this, I fear you are taking your life in your hands.
Normal pressure cookers add a maximum 15 PSI to achieve a water boiling point of 121 C or 250 F. Autoclaves, used for surgical sterilization, go to 30 PSI. You are talking about going more than twice that.
There is no reason, based on the science of Maillard reaction, to believe that it would not occur at a high enough temperature. The presence of excess water would normally inhibit the process because of temperature reduction, but your "super duper pressure cooker" would keep the temperature at a high enough level to allow the chemical breakdown to occur. You might, in fact, discover that it occurs a bit earlier, as water tends to facilitate many reactions. Caramel making comes to mind as an indicator of what might be achieved, as sugar syrup (OK, most of the water is gone, but in principal) browns when you get in the above 330F-165C degree range.
As to crisping based on quick pressure reduction (perhaps when your device explodes?) That seems less likely as most crisping comes at the loss of water, and you are, in effect, keeping water in contact with your food both in liquid and superheated steam form. It would, most likely, be similar to a braised food surface, than a fried one.
Interesting thought. Please don't try this.
Eye of round is very lean. Very, very lean. So as a steak, it would not stand up very well to any cooking method that gets it much beyond rare. And even then, it's going to be a tough piece of meat. My suggestion would be to prepare that cut differently (such as macerating it and making country fried steak or Swiss steak), or omitting it from your rotation. Your method is sound for preparing a steak, but I would limit it to:
- Tenderloin
- Strip
- Ribeye
- Chuck eye (not chuck steak, which is a tough piece of meat, but chuck eye, which is cut from the eye roll).
If you want cheaper beef, the last in the list is your best bet.
Best Answer
I'm afraid you have gotten something wrong.
Sous-vide and pressure cooking are, as far as food physics is concerned, on the opposite ends of the scale.
Pressure cooking allows you to increase the boiling point of water, thus reducing the cooking time. (Bad idea for a tender steak, btw., as soon as you exceed a certain temperature, the proteins in the meat change irreversibly and the meat gets tough.)
Sous-vide uses temperatures way below the boiling point, combined with a very extended cooking time. This means you can safely and slowly bring your steak to the desired core temperature without the risk of overcooking and thus toughening the meat. A final sear is just a finishing touch, not technically a necessity for cooking the meat. (But don't skip it, it's for flavour and eye appeal!)
So no, we can't give you a temperature / time chart for steak in a pressure cooker - because the results would be very unsatisfactory.