From the instructions:

The pressure switch, if supplied, is set at its' minimum setting(approximately .5 psi) It has an adjustable range to 4 psi.

i am waiting on a AFPR and a Wallbro255 to dump the Vortech and stock FPR. It will take a couple more weeks. In the meantime, due to the IC effectiveness, the Vortech can only supply enough fuel to deliver 11.5 AFR's when I reach 3PSI.

That means while progressing between 0-1-2 psi, I go lean, say 13.5 or higher. This takes only a second in high RPMs, but if I pull from low RPMs its a longer lean tip in and I dont want to take any chances.

So, I took out the vacuum line connecting to the pressure switch and blew into it while idling at 14.7. it takes aprox 4/5 seconds to go from 14.7 to 11.0
What I am thinking is to set it to kick in earlier, just to be safe untill the AFPR arrives.

If I bring the screw outside the casing surface can I set to start working in atmosferic pressure, or 0.5 psi is really the minimum setting as the instructions say?

 

Backing it out a little above the housing will drop it to almost -0-, but it will not go below -0-.

The 4/5 seconds at idle is probably a combination of delay of the ecu reading the low voltage and the air column getting to the O2 sensor.

 

thx Bruce, you mean while driving the clamp will be doing its work faster due to EG reaching the 02 sensor faster?

 

The clamp won't be working faster, but with a larger volume of exhaust, you will be reading it sooner.

 

thx. not sure if it will help as my main problem is when flooring it at low rpms, but will try it. cant hurt.

thx again