I have a aluminum 225. Head is original stock with the surface milled -.06. I have an automatic tranny and a comp cam part# 64-240-4. I have played with my timing going from 5 to 25 degrees and it seems to run the same no matter where I set it. It runs pretty good but I want it perfect. I have an ever so slight surge at a constant speed. What should the timing be set at? I also have an Edelbrock 500 carb. Can anyone give me a good starting point on where to set the 2 mixture screws that are on the front of the carb? If you need more info please inquire.