Thermostatic oil adapter

[ERA Chas]

My problem concerns Mocal thermostatic Sandwich adapter, pn SP 1 T, used on my 427 SO. The system includes; Earls cooler, AQ lines and fittings, Mobil 1, 10W-30, and Melling HV pump with Canton RR pan. The motor is seasoned and well broken-in. When starting engine cold, the cooler and fittings will become warm to the touch very soon. This indicates that oil is circulating to cooler immediately. The oil t'stat is a 180 deg. design . The SW oil temp gauge shows no reading at this point, [gauge rstarts at 140 ] and has tested as accurate. Warm-up water temps of 160-170 deg. will bring mild oil temps to the cooler. The WATER t'stat is a 190 deg. which works correctly and brings water to 195-215 even on 90+ deg days. It also maintains temp on 40 deg. days . When brand new, I tested the oil t'stat by the old pot-of-water-to-boil-method. The t'stat opened just before boiling which seems correct, and closed as cool-down took place. I can get oil temp on 60 deg ambient days and/or with elevated RPM, which I HATE to do on cold oil. See? Catch 22. I just don't think t'stat is working on the motor as it did in the pot. I bought it from the kind folks at Racers Wholesale but they were only able to provide the phone of Mocal USA in Fla. The tech line could only provide the correct orientation of the in/out line fittings [which I took pains to get correctly], but were no further help. Sincerely appreciate any advice or similar experience to correct this problem. Thanks for your help.