Changing Fuel Pressure with Computer?

I am getting a cam installed next week and I was wondering that if the car would happen to run rich or lean after the swap; can the fuel pressure be changed via my diablosport chip on the dyno or would I need a fuel pressure regulator? From what I've heard a fuel pressure regulator for our cars would be uneccessary because the computer will reverse any changes you made to fuel pressure over time. Thanks for any help
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Fuel pressure is regulated via a physical device, being the fuel pressure regulator. If you do alter the stock settings, the computer will compensate with its adaptive strategy to attempt to bring you back to the stoichiometric 14.7:1 air fuel ratio. If you deviate too much from the stock pressure and decrease your pressure, you may end up bringing the computer to its adaptive limit. Being a tad rich wouldn't necessarily be a bad thing, but I'd bet you'd probably be just fine at the stock pressure. If you decide to make any changes to the tune, you need to take it into account when making any alterations, because more pressure makes the injectors run as though they're a larger size. My opinion is always to keep the factory pressure, or as close to it as possible, for ease of tuning.
You CAN raise FP to make the injectors act like bigger injectors at WOT. But you will fight the PCMs 'job' to keep the A/F at 14.64 at idle and part throttle. In fact if you go too high with FP you'll throw codes because it'll only trim values about 20-25% or so at idle and part throttle. Without the right things changed in the tune, these adaptive values will also be applied to WOT. So really the 'old school' method of tuning via FP isn't really such a great idea.