ok, after a little more thought, I think you are right and wrong at the same time. You say that you need an adjustable regulator because your injector size can not support your fuel needs at the factory 39 psi. This is correct and makes perfect sense. Crank the pressure, and you will get your increased fuel.
But why wont this also be beneficial to people with minor or moderate mods? I guess it comes down to defineing moderate and minor mods, horsepower numbers, etc...,
but, if for example, a car needs 26 lph to run ats its best power, and they have 24 lph injectors at 39 psi, it wont perform its best.
So, they slap on a adjustable regulator, crank it up a couple psi (the exact desired psi number is based on formulas, specific fuel comsumption, blah, blah, blah, etc...) to experiment, and the car performs better. Now, everythings cool, the car needs slightly more fuel for its particular combination, and now it has it, why would the computer even attempt to change anything? The car runs good, and maybe it is at the desired air/fuel ratio determined by the computer, so it has no need to revert back or change anything. Possibly the desired air/fuel ratio wasnt available with the factory computer programming, injector size and fuel pressure, but now it is. So, in essence, you are just "helping" the computer, not "tricking it" or "changing it", and it likes it, why would it try to change anything?
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1993 GT/AOD
'93 Mustang GT