the original engine. 5 or 6 quarts? I put in 5 quarts and let it run. It seemed okay, the oil pressure was at about 50. Then I drove it around and at idle the oil pressure goes to 20. When I drive, it goes to 50 again. I checked the oil stick, but the oil is just to transparent to make a good call. Does it need 6 quarts? And, if so, did I do permanent damage to my vehicle by running it with 5 quarts?