to get a 50hp gain your going to need to run atleast 10psi boost
3-4psi will only get you 20hp
stock 451 turbos run up to a max of 7 psi approx depending on conditions, but as an average 5.5psi is what you normally get.. you can not increase boost to more than 9spi as the computer is out of range and no matter how much tweaking is done...
in reality the power outputs claimed and even so called dyno proven are inflated... its easy to lie to the dyno and get a higher Hp reading
in the pics it also appears that the setup isnt intercooled, there will be massive inlet temps especially after heatsoak, might wanna look into a cooler for it..
whats turbo is being used for the kit?