What kind of air compressor do I need for an HVLP spray gun?

What kind of air compressor you need for an HVLP spray gun depends on gun requirements, but generally you need a large, high-CFM compressor, not small pancake compressor, because HVLP requires high volume low pressure. Most gravity feed HVLP automotive spray guns require 10 to 15 CFM at 40 PSI and 25 to 30 PSI at gun inlet with trigger pulled to properly atomize basecoat and clearcoat, which means you need at least 20 to 30-gallon tank compressor with 2 to 3 HP motor and 5 to 7 CFM at 90 PSI rating that can deliver 10 to 15 CFM at 40 PSI. Small 6-gallon pancake compressors delivering only 2 to 3 CFM at 90 PSI are not enough for full-size HVLP and will cause pressure drop, poor atomization, and compressor running constantly. For professional use, 60-gallon 3 to 5 HP two-stage compressor delivering 15 to 20 CFM at 90 PSI is ideal. You also need clean, dry air, so use water separator and filter. LVLP guns are alternative needing only 3 to 6 CFM, so they work with smaller compressors. So for HVLP, need at least 20-gallon 2 HP compressor delivering 10 CFM at 40 PSI, preferably 60-gallon 3 HP for continuous spraying. Check gun spec, Black Widow HVLP needs 9 to 13 CFM, Devilbiss similar, Iwata needs 10 CFM.