I saw that someone did a pre-setting of an adjustable fuel pressure regulator using an air compressor. The thread was called "Vacuum Adjustable TBI Fuel Pressure Regulator" that had a statement in "There was a guy here awile back who dialed in fuel pressure on a TBI on bench with air pressure. Pretty sweet setup he made from parts laying around. Was same pressure in truck with fuel when he was done."
Has anyone else done the air test to find out what pressure the regulator is running at with a TBI set-up?
I built an air fed system used things I had around the shop and an inline fuel pressure gauge. I used an adjustable pressure regulator to feed the TBI because I was pretty sure I should not be forcing 120 PSI through the TBI regulator.
When I set the air regulator set to 17 psi, the fuel gauge reading at 9.5 psi.
When I set the air regulator set to 22 psi, the fuel gauge reading at 10 psi.

What air pressure should I use when testing?
Should I be using the same pressure as the max output on the fuel pump?
If so what is that on a TBI system?
Thanks, Mark J