I wish I could tell you. I just don't know. I bought this car from the uncle of the young man that had the engine work done. He didn't know what all was done. I know he put a set of Aerohead S.B. heads on it. It has a Performer RPM w/ 600 Eddy carb, MP electronic ignition, and Headman headers. It runs very strong for a 318. It had a 4:11 with a manual valve body when I bought it. I changed both. It now has a 3:23 and fully auto trans. I was told it ran high 13's the way I bought it.