Just to make sure I got this right, after Snap does a 4-flip he does NOT get his free boost action due to stress after his maneuver despite his free boost ability after a 2,3, or 4 speed maneuver. Thanks
Snap Wexley and his 4k turn
Correct.
He can equip Primed Thrusters or Pattern Analyser and still get it though.
"Check pilot stress" is part of executing a maneuver and Snap's ability says "after executing a maneuver" so the stress would come on before his ability would trigger which would normally prevent it unless you have one of the aforementioned upgrades.