i am finishing up a half bridge rebuild and was wondering if i should upgrade my injectors. i am using p-720cc and s-1100cc right now. i will be running a gt45 on a half bridge. im planning on 400-425whp. if so, what size should i use?

 

720/1100 injectors are good for about 380-445hp at the flywheel. I think you are going to need to swap out your 1100cc secondaries for 1680s in order to support 500hp at the flywheel.

A Garrett GT45 turbo is entirely too large for your application.