Hi i live in australia oldsmobile were not sold here so it is hard to find people who know much about them . i have a 1950 mercury coupe when i bought it, it had the engine already changed from its original flat head motor to a oldsmobile v8 . i dont know what size it is what year it is or what it came out of . can anyone help me out . tell me what to provide you and ill get back to you asap. thank you