99 7.3 turbo won't boost
 

99 f350 dually w/7.3 powerstroke will not boost. I replaced 4 injectors on drivers side with used out of other engine I have. Replaced fuel pump and cracked lines because of fuel leak. Engine runs great but still will not boost. Mechanic says I need 8 injectors for the turbo to boost. Something about not enough fuel going through injectors. Any truth to this??