Look inside the upper where the throttlebody bolts on. HO uppers have a 60mm opening and non-HO uppers are only 50mm.All HO uppers will say HO or High Output on the top cover plate while non-HO plate will just say 5.0 EFI.
All 5.0 lowers are the same.
Those injectors are only 14lb and the Crown Vic ecm is a speed density system calibrated only for the 14lb injectors. HO injectors are yellow and are 19lb whether they are used with a speed density or mass air system.
The Crown Vic ecm and injectors are only rated for about 175hp where the HO stuff is 225hp.
Last edited by deathbypsi; July 5th, 2011 at 05:46 PM.