After the first step of my Mystic 400 (40cm length cf page 9) there is the second one
, 45cm length and now the speed is 91km/h
(X430/R-2xLeo 2040/4450kV-3S/1000), with a run with an average speed of 88km/h for 100m.
Two pictures and one video at 82 km/h (K31-2xHK 2040/4800kV-3S/1000) :
The full scratch build of this version starts here