I don't know.... A 57 235 should be a full flow oil filter system already and have inserts not babbits, so your oil pressure should be between 20-30 lbs at 30 mph. When I rebuild 235's I always replace the old oil pump with a Melling high volume/low pressure pump. You really don't need high pressure in a 235. If your oil pressure in a 57 engine is running in the single digits it is either a wornout engine (main, rod and/or cam bearings are bad) OR the oil bypass in your oil pump is bad. Your oil pump is the backbone of your engine.
