Does anyone know the correct operational psi ranges for both the low and high side ports? I've been searching the internet for hours now with no luck.

 

Idling with the A/C fans on low speed the pressures will be roughly:
28-30 psi, low side
150-170 psi, high side

Kick the fans to high speed:
35-40 psi, low side
190-210 psi, high side

That would be at ambient temps around 75 deg. F, higher temps would mean somewhat higher pressures, and cooler temps a little lower.

Hope that helps.

 

Thanks Steve, it's a huge help. I just couldn't find it anywhere, even on my service manual cd.