Red Cube Factor?

What have others found that works best with their Redcube installation? FWIW My Redcube, on a Lycoming O360, seems to work best with a factor of 66,200 not the 68,000 indicated by the manufacturer.

Just curious.

I think mine settled in at 69075 after a few hundred gallons and little tweaks

I chased instability for a while; the length of hose (inlet) and the additional 90° at the pump outlet seemed to be causing issues.

YMMV

68000 is a good starting point for the FT-60 (red cube). Depending on what parts were used in the installation (hoses, fittings, etc), an adjustment to the k-factor may be required and is not uncommon.