My setup will be different from yours as I run a blower and a stroked 347. Choose a map that is close to what you have or combine a few. Run a WIDE band 02 sensor so you can see why you have lag. Use a passenger to read the data when the lag accures or use the data logger if by yourself. If you have a large dip or hump in the map smooth it out, dont take large steps in fuel. Look at some of the maps that came with the program, ford or chevy and see how they compare to yours. If your fuel map looks good then check your timing map and so on.