Your pressure is perfectly normal for your vintage of Benz. My 4.5 shows almost exact numbers running 30W dino, ~25 at idle and pegged underway.

__________________
Mike Tangas
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72

'02 CLK320 Cabriolet - wifey's mid-life crisis

2012 VW Jetta Sportwagon TDI...at least its a diesel

Non illegitemae carborundum.