HVLP guns require lots
of air. Typical specs are 10-15 CFM Here's an article
on picking a HVLP compressor.
Here's the specs for a HVLP gun.
HVLP stands for high-volume, low-pressure, and spray guns incorporating this technology give you better, more consistent coverage than conventional spray guns, and with minimal messy overspray.
High volume, low pressure (HVLP) material transfer
Designed for automotive/industrial use
20 oz. gravity feed gun with 1.4mm tip for top coats, 1.8mm tip for primers
4.3 oz. detail gun with 1.0mm tip
Kit includes: paint filter, two bristle brushes and one wool brush for cleaning, plus durable blow mold storage case
Required air supply: 1-3 HP compressor
Required pressure: 30-35 PSI (large gun), 25-30 PSI (small gun)
Average air consumption: 12 CFM @ 43 PSI (large gun), 9 CFM @ 43 PSI (detail gun)