Go to http://www.chevytalk.org/cgi-bin/ubbcgi/Ultimate.cgi and go to the EFI page. One of the people responsible for designing the holley system (Doug F) answers questions about the holley system. There are quite a few knowledgeable EFI people on this board, and they have probably covered every question you have (and some you didn't think of yet). Another person on the board (Grape Ape) has his own web site that covers a lot of EFI topics in detail - you might want to look through it.