This.... The are different part number P.C.V. valves, for a reason. The lower compression early 70's - 80's engines ,usually ran less vacuum.(The bigger cam, reduces vacuum similar to these engines) Do you have a part number stamped, on the one you are running ? Where I would start, with a good driver in seat (automatic trans) ,looking for peak vacuum in drive, about 900-1000 rpm. Timing at least ,14-18 initial,34-36 total. @3000-3500.(General information, makes my turds wake up)
