My 502 came with 14 degrees of initial on spec sheet....Mine is from early 90's Bought from dealer. ...Was a update made on later builds, as I has seen 9 degrees of initial spec on other spec sheets. ...... All parts were used as Delivered to the dealer. I'll try to find the parts list as supplied with, the motor in the crate. Keep all paper work. Magnesium covers that were made when, Warren Johnson was running Nhra Olds I Machined adapter plates.