EZstruder spring enhancer

I was having issues with my EZstruder slipping trying to grip filament so I wanted to increase the grip by increasing the tension caused by the spring. So I just created a 2mm spacer that the spring can rest on.
It gives it enough torque now that if it's being told to extruder, but gets too much "backpressure" from trying to extrude too much for the motor to handle the motor will skip, instead of the filament slipping.

I had previously tried a 3mm spacer but that caused too much torque and a failed print after 3 hours :(

This 2mm spacer though I have successfully ran a 12 hour print ( the vase above) with a .5mm nozzle at .15mm layer height at 88mm/s. If there was any filament slippage it definitely wasn't obvious from the print, it turned out GREAT!