Is there a difference in HVLP and Gravity fed? I have a Devilbiss Finishmaster which is titled gravity fed. All the tech data sheets show psi ratings/instructions for HVLP and non-HVLP. How is gravity fed related? Thanks.

Guns are of two types, with two or three sub-types, if that makes sense....

Guns are either Syphon feed (cup on bottom, airflow syphons paint out of the cup) or Gravity feed (cup on top, paint flows into the airstream by gravity).

Either type above can be non-HVLP, HVLP, or Sata's newest line, RP for reduced pressure.
To be HVLP qualified, the gun must transfer 65% of the material to the surface sprayed. Quite a few areas of the US now have requirements to use HVLP only.

Personally, I have guns of both types, HVLP and non-HVLP. All are gravity feed. I have found that my non-HVLP gun sprays the newer thicker clearcoats better than the HVLP guns I have, and in all actuality, the Non-HVLP gun really doesn't use much more clear than my HVLP guns would on the same size panel.
The right gun for you is the gun you can spray well with. I use Iwata guns for basecoat, and I have an old DevilBis Gravity fed HVLP gun I use for primer and sealer, it has a little bigger tip. My clearcoat gun had also been an Iwata non-HVLP, but I recently replaced it with a (don't laugh... :D) $130 Cornwell HVLP gun, believe it or not, it sprays awesome. Took a while to get it set to spray the newer thick clears, but I won. :yes:

So if the paint tech information states the following....

Air Pressure: 6-9 psi at the cap with HVLP equipment and 25-45 psi for non HVLP equipment

Should I shoot at 25-45 psi with my gravity fed non HVLP?

Thanks.