New Intake, Brake Problem

[5.0 Pony]

I recently bought an 88 5.0 lx vert and have been looking to do some mods. I already have cold air induction and i want to add an intake next. The problem is which one to add? The Cobra intake, Gt-40intake, Edelbrock Performer intake or a Trick Flow Street Heat? Any experience with these. Which one gives the most bang for the buck? Also when i drive i can hear something knocking, its not like i threw a rod though. Its more like the front calipers are lose and are rattling, but i checked them and they are tight, also i can feel it in the pedal when i brake from about 60 mph + . And it only does it sometimes not all the time, but there is always a definent knock when the brakes are applied and released. What do u think new pads? Well any help would be greatly appreciated. THANKS!