Thanks all. I weigh 160 lbs and right now run 40 psi using Schwalbe CX Pro which is 30mm. Coming from road it just "looks" too low.
The CX guys on my team are saying i should go 30-35 psi for better rolling resistance which seems counter intuitive since higher PSI has lower rolling resistance or tarmac at least.
So with 33mm tire can i go lower than 40 PSI?