They don't do well with cold fuel much less with cold wmo. I wouldn't trust the holley on the engine compartment, but right next to the fts is a better fit since they seem to push better than they pull. I have the carrier right now and it is very close to the IP but the pressure doesn't build up until after the engine is warm
I wonder if maybe the Facet would do better pushing? I may rethink my set up and move it down lower. Mine runs 6-8psi right off the bat ( we're in the 30*s here). May have something to do with differences in the Ford and Chevy plumbing?
As for enlarging the ports, I was only able to do the input side as the output fitting in the pump can't easily be opened up. There's been 2 failures with these pumps, both, I believe, were running WMO and the pumps were up higher. I wonder if running it down lower might be the key?
I did check with my supplier, and he really doesn't want to get involved with warranty issues
But you should be able to take it to a Carrier dealer. Wish I could offer more help.