Cheap FPR mod - adjust timing or not?

I am gonna try to put a bit more fuel flow into the injectors...

Fuel pressure regulator with a vacuum solenoid valve turned on/off by a switch inside the cabin...

Basically the valve will work in bypass mode until switch goes in to block the vacuum going to FPR diaphraghm - giving more fuel onto the rail...

for the extra 10-12 psi, is there any point to change the timing on the fly?