Added 8 inch crank pulley

I have added an 8 inch crank pulley now, how do i determine the correct size injector now? I know (close) to what the car was running with stock pulley about 5 lb boost and about 400 hp at the wheels or close. I am currently using 24lb inj, with an FMU. From what i read on here i should just go to 42lb inj.?? Its above the B.S.F.C. rating. What is the best for drivabilty and over all performance?? If i go with the 42 lb'ers will my start up and fuel econ suffer? ( not that i really care about fuel economy) I see alot of people go with this injector but is it to allow more room to grow with their setup? I ,like everyone else will keep adding to my setup at some point in time,just dont want to buy something i will have to upgrade later when i can do it now.

this is sorta a repost but i always like to double check anything i do!!

The 42's will work nicely. Once its tuned with the same A/F ratio as you have now the fuel economy should be the same, because the injector duty cycle will be lower than with the smaller injectors.