[MinnesotaDave]

Just curious, why not buy another complete compressor and tie them to the same line?

I run multiple compressors when needed, and just my main one when that's all I need.

I've looked at compressor heads with motors in the past and found them to be too expensive when compared to buying a complete unit.

 

[MinnesotaDave]

Cheaper and easier to just set the cut in pressures on the two compressors about 10 or so psi apart, so one has time to get up to speed before the other needs to kick in. Then also have the cut off pressures set at different pressure, so one cuts off, then the other as they come up to full pressure. No need for a delay timer when done this way. The delay is set with the pressure settings.

That's how I run mine. If the big one keeps up, the other ones don't start up.