R134a system pressures
 

I have the service manuals for my 1992 svx which lists the standard pressures for r12 ac.
My system has been converted many years ago, but I am wondering what are the standard pressures for high and low for a r134a system?
I know pressure varies with temp, and if you have a graph or spreadsheet for pressure vs temp that would be great, but the service manual I have only lists standard pressure.
Thanks.
Bill Z