LT1 fuel injector size?

[Ed Wright]

There are fast LT1 Stockers running 24 lbs and 30 lb injectors. Personally I would use the 24lbs at 60 psi. Higher pressure atomizes the fuel better.
As far as Alpha N or Speed Density, that has no influence on required injector size. And, you can select any size you want with FAST XFI or BS3. Just type in the size you have. Remember to correct that value if you up the fuel pressure as that increases the injector flow rate.