[mpg200]

Hi,

A savox will pull spikes of 3.5A which can upset weak BEC circuits causing the receiver to 'brown out' (glitch)

The capacitor on the speedcontroller is there to handle the ripple current so the large ripple is not seen by the cells, having this diconnected will cause high ripple in the cells which can cause the speedo to brown out.

So replace the cap/caps on the speedo, yes if you have space you can add 2 together.

This together with keeping the receiver capacitor should solve your problem.
I run spektrum and savox with 2200u 25V cap on the receiver (rubycon ZLH series I think) i'll check.
I have no issues with brown out on Durango 410. My speedo is a Nosram matirx which although is rated at 3A BEC, I know its good for 4A I tested it. Won't do 4A for long though I had it run 4A for 3 min continuous, it got a bit hot.
As for a speedo cap, I've used 1600u and 2200u and they have all been fine. but the bigger the better just make sure its at least 16V better if its 25V. use ones with low internal resistance Rubycon ZLH for example.