On 2009-11-30, Bruce L Bergman wrote:
The smart way is to get the Constant Run Unloader assembly from
Quincy, which will involve a special head with pistons to hold the
intake valves open to eliminate pumping losses. And a second air
cylinder that drops the engine back to idle when the head is unloaded.

Just a little by the way, I made my Quincy compressor run in both
Run-On-Demand, as well as Constant Run mode. It is switched by a DPDT
switch.

http://igor.chudov.com/projects/Quin...-vs-On-Demand/

In reality, I need constant run only when I am sandblasting, which is
rare.

i