Just bought 2 cases of Brad Penn. Had a lengthy discussion with Bob Rahilly (Rahmoc Racing Engines)in North Carolina about motor oil. He mixed 2 cases of 15W/40 for me. I believe this old Kendall refinery oil is the best we can get right now. It is the same Kendall GT-1 of years ago. Call him for info. (704) 782-1175. Reasonable pricing and fast shipping.